Full text of "Tornadoes, what they are and how to observe them, with practical suggestions for the protection of life and property"

See other formats

THE LIBRARY OF THE
UNIVERSITY OF
NORTH CAROLINA
AT CHAPEL HILL

ENDOWED BY THE
DIALECTIC AND PHILANTHROPIC
SOCIETIES

QC955

UNIVERSITY OF N.C. AT CHAPEL HILL

1000108727

Digitized by the Internet Archive
in 2014

https://archive.org/details/tornadoeswhattheOOfinl

TORNADOES.

WHAT THEY ARE AND HOW TO OBSERVE THEM;
WITH PRACTICAL SUGGESTIONS FOR THE PROTECTION
OF LIFE AND PROPERTY.

JOHN P. FINLEY, M. S., F. S. Sc.

Lieut. Signal Corps, U. S. Army ;
Honorary Fellow of the Royal Society of Science, Letters and Art, London ; Member
of the Societie Meteorologique de France, Paris.

NEW YORK :

The Insuranxe Monitor.

1887.

Entered according to Act of Congress, in the 3^ear 1887, by C. C. Hine, in the
office of the Librarian oi Congress at Washington.

The important information set forth in this book is the result
of many years of labor and the examination of more than five
thousand storms. Ascertained facts have been taken as the
basis of every statement, and it is believed that, while further in-
vestigation may add truth to truth, it will only set more strongly
the seal of authority upon what is here presented concerning
the special characteristics of tornadoes and the great dangers
which accompany them, augmenting the practical knowledge
thus far obtained regarding the protection of life and property.

THE AUTHOR.

TABLE OF CONTENTS.

PAGE

Tornadoes Peculiar to America 7

Chart No. i, Showing Geographical Distribution of Tor-
nadoes facing page 7

Cyclones 10

Hurricanes 13

Whirlwinds 14

Waterspouts 15

Hailstorms 16

Thunder-storms 17

The Tornado ; its Definition, Conditions of Formation, etc. 19

Premonitory Signs 25

Illustrations of Tornado -clouds 27, 29, 31, 33, 36, 37, etc.

Protection 43

Suggestions for Escape 44

Plan for a Tornado-cave 51-65

Illustrations of Tornado-cave 54, 56, 58, etc.

Descriptions of Individual Tornadoes, with Numerous Illus-
trations 69-100

Tornado in Saline County, Kansas 69

Tornado at Lee's Summit, Missouri 78

Tornado in Marshall County, Kansas 86

Tornado in South Carolina 95

Chart No. 2, Delineating Course of Progressive Movement,

facing page loc

Tabulated Statistics of Tornado Observations 104-144

Summary of Results 145

Scientific Resume of Tornado Characteristics 147

Instructions for Observing Wind-storms 169

General Instructions to Volunteer Tornado Reporters 189

TORNADOES,

Lieut. John P. Finley, U. S. A.

The people of the United States are no longer strangers to"
that dreaded aerial monster, the Tornado. A single experi-
ence of this awful convulsion of the elements suffices to fasten
the memory of its occurrence upon the mind with such a
dreadful force that no eff'ort can efface the remembrance of it.
The destructive violence of this storm exceeds in its power,
fierceness, and grandeur all other phenomena of the at-
mosphere.

For over two hundred years past the scientific records of
this country have furnished information concerning these
storms. It is the same fearful story year after year, of destruc-
tion and death, and the records are now sufficiently complete
to show beyond all contradiction or exception that tornadoes
are indigenous to this country. They belong here because
our geographical position and the topography of the country
are altogether favorable for the conditions which give rise to
their formation. No other country in the world is scourged
by them as is the United States of America. If our broad ex-
panse of country was cut up by mountain ranges running in
every direction, forming a network over the vast plains of
the West, and cutting up like a checker-board the great valleys
between the Appalachian and Rocky Mountain ranges, then

topographical conditions would intervene and present formid-
able barriers to the direction and effect of surface currents.
These conditions, if they were present, would well nigh rid
the country of the funnel-shaped cloud. Fortunately — or un-
fortunately, we are not to say which — there are no natural barri-
ers to the development of tornadoes in the greater portion of
the United States. Their geographical distribution is graphic-
ally presented by chart No. i (see frontispiece), and the effect
of the Appalachian chain of mountains, and that of the
Rockies and the Sierra Nevadas over the vast stretch of
country west of the looth meridian (Greenwich) is strongly dis-
played on the chart and the argument set forth is conclusive.

The populous region of the United States is forever doomed
to the devastation of the tornado. As certain as that night
follows day is the coming of the funTiel-shaped cloud. So
long as the sun shines upon the vast regions in the Mississippi
and Missouri valleys, there will forever occur those atmos-
pheric conditions which terminate in the destructive violence
of the tornado. Nature's laws are unerring in their certainty
of procedure, the earth must travel in its orbit about the
sun and the seasons must recur in regular sequence as the re-
sult of this wonderful periodicity of movement. The earth
must revolve upon its axis, and daylight and darkness, heat
and cold, must succeed each other with infallible precision.
Without these great and regular mutations dependent upon
the solar system, atmospheric phenomena would cease alto-
gether. Granting that the solar system must continue intact,
we have but to watch and protect ourselves as best we may
against the fury of the elements. Ignorance of our surround-
ings is a most unfortunate plea for those who stubbornly fail
to heed the warnings of science. Thousands of people com-
fort themselves with the thought that as they have escaped in
the past, so will they always remain free from danger; but a
knowledge of the tornado, and the necessary precautions to
be taken for purposes of safety, should be as common and

familiar to the people living in tornado districts as a knowl-
edge of the ordinary methods of extinguishing fire. Every
effort should be made to popularize the information on this
most important subject.

In spite of all that has been written and published about
tornadoes in the press, in scientific journals, and through the
Signal Service, much confusion prevails regarding the appli-
cation of the term and the distinctive character of the storm.
This confusion leads to a most unfortunate disregard of cer-
tain necessary provisions for safety which should not be
neglected by people residing in the tornado districts. Under
the head of wind-storms there are various atmospheric
phenomena, severally designated as tornadoes, cyclones, hurri-
canes, whirlwinds, waterspouts, hailstorms, and thunder-
storms, which are essentially distinct in their characteristics.
While they are all seriously destructive in their effects, there
are many differences which give rise to modifications in their
development which it is of importance to know. All of these
storms are more or less destructive to life and property, there-
fore means of protection should invite the earnest attention of
all people.

The coming and going of these storms are as certain as
death, yet adequate means of protection for the body and
for property are strangely ignored ! A practical knowledge of
the various kinds of storms known to the United States
should be one of the subjects of instruction in our public
schools. As the country increases in wealth and population,
which it now is doing with wonderful rapidity, the danger to
be apprehended from the violence of wind-storms is ap-
palling. Formerly, these violent meteors left no mark upon
the treeless and uninhabited prairie, or if passing through the
wooded regions there remained but the ''windfall" to denote
the track of the monster, but now the farm-house and the
village dot the plain, and the hardy laborer has forced his
way with his family into the depths of the forest. Where, years

before, there were but inanimate objects to mark the fury of
the tornado, precious lives and hard-earned property now
succumb to its violence. The funnel-shaped cloud with its
tail lashing the earth must now pursue a most tortuous course
to avoid the farm-house and the mill, the schoolhouse and
the church. The best evidences of civilization and material
prosperity suffer untold misfortune, and must continue to do
so while our earth has an atmosphere and the sun shines
upon it.

This state of things, which upon first consideration may
cause alarm and discouragement, should upon reflection give
rise to courageous efforts in the direction of securing in-
demnity from loss of property, and establishing provisions of
safety for human life. The protection of life and property
from fire, shipwreck, and disease has compelled the growth
of institutions under State authority which afford a safe and
generous indemnification in case of loss ; a similar necessity
in the event of destruction by wind-storms must call for the
growth and support of similar institutions.

I have previously referred to the necessity of a practical
knowledge by the people generally of the various classes of
wind-storms, particularly the tornado. It will not be amiss
here to give a brief description of those phenomena, point
out their differences, and then follow with a special discus-
sion of the tornado.

CYCLONES.

A cyclone is not a tornado, either in the perfection of its
development, or in any stage of its formation and progressive
movement. The two storms are essentially different. The
cyclone possesses the following characteristics: The path of
the storm is a parabolic curve. It trends northwestward from
the West Indies until it reaches parallel 30° N. when it curves
to the N. E. and continues in that direction, either at some
distance off the Atlantic coast, on its immediate border, or a

short distance inland. The storm finally disappears ocean-
waid in the vicinity of parallel of 50° N. The diameter of its
path varies from several hundred to over one thousand miles.
At the immediate center of the storm there is a dead calm, a
most fatal place for ships to be caught. At no point without
the storm's center does the air actually move or whirl in a
circle, but there is a cyclonic tendency of the atmosphere
about the region of barometric minima, viz.: where the
barometer is the lowest. Upon taking a number of points,
located here and there in the four quadrants* of the meteoric
disturbance, it will be found that in the northeast quadrant
the winds vary from southeast to northeast ; in the northwest
quadrant from northeast to northwest ; in the southwest
quadrant from northwest to southwest, and in the southeast
quadrant from southwest to southeast. The barometer is a
veiry important factor in all calculations bearing upon a
determination of the character and approach of the cyclone at
any point in the parabolic course of the storm. The wind
very rarely reaches either an estimated or measured velocity
of one hundred miles per hour. The maximum velocity gen-
erally ranges from sixty to eighty miles per houn As a rule
there is no sudden, overwhelming dash of the wind, but a
gradual approach or increase of movement which eventually
culminates in a fierce intensity sufficiently powerful at times
to destroy buildings or sink the largest ships. Cyclones
occur most frequently in the months from August to Novem-
ber. In the China and Japan Seas this class of wind-storms
is called typhoons. In general, as to their place of origin,
cyclones form south of the Tropic of Cancer, between the belt
of calms and the southern limit of the trade-winds ; say,
briefly, in the vicinity of 10° N., 50° W. This region co-
incides with the zone of constant rainfall, where evaporation

* Quadrant ; the fourth part ofa circle. In describing wind-storms, etc., it is cus-
tomary to speak of the area alluded to as divided into four " quadrants the north-
east, northwest, southwest, and southeast.

is very rapid, cloud formation exceedingly brisk, the lair
almost constantly saturated with moisture, and heavy con-
densation a regular feature of the day. Typhoons form
south of the Tropic of Cancer and in the vicinity of the
Philippine Islands, moving thence northwestward to the Asiatlic
Coast and then curving to the northeast over the adjacent seas
and islands. As to the character of the region in which th^y
form, the same remarks apply as in the case of cyclones.

TORNADOES.

The tornado is truly and invariably a land-storm, which we
find possessed of the following prominent characteristics : A
path varying in width from a few yards to eighty rods. T^e
general direction of movement of the tornado-cloud is ii:i-
variably from a point in the southwest quadrant to a point
in the northeast quadrant. The tornado-cloud assumes the
form of a funnel, the small end drawing near to or resting
upon the earth. This cloud, or the moving air of which it
is the embodiment, revolves about a central, vertical axis
with inconceivable rapidity, and always in a direction con-
trary to the movement of the hands of a watch. The
destructive violence of the storm is sometimes confined to
th^ immediate path of the cloud, as when the small or tail
end just touches the earth While, on the other hand, as the
body of the cloud lowers, more of it rests upoh the earth, the
violence increases and the path widens to the extreme limit.
The tornado with hardly an exception occurs in the afternoon,
just after the hottest part of the day, and generally disappears
before the going down of the sun. The hour of greatest fre-
quency is between three and four p. m. A tornado very
rarely, if ever, begins after six p. m. , but a tornado commencing
about five p. m. may coniinue its characteristic violence until
nearly eight p. m., which only means that the tornado-clouci
may be traveling after six p. m. or after seven p. m., but it does
not develop, that is, make its appearance for the first time,:

after those hours. Without the path of destruction, even to
the shortest distances, at times even along the immediate
edge, the smallest objects often remain undisturbed, although
a few yards distant the largest and strongest buildings are
crushed to atoms. At any point along the storm s path,
where there is opportunity afforded the tornado-cloud to dis-
play its power, the disposition of the debris presents unmis-
takable signs of the revolving, right-to-left action of the wind.
The violence and intensity of the destructive power increases
directly as you pass from the circumference of the storm to its
center.

Observations with the barometer are of little practical value
at any one point, whether made before or after the tornado-
cloud has formed or while it is approaching. Such observa-
tions will not indicate its approach, however near the position
of the instrument to the point of the cloud's inception. The
' ' tornado season is embraced between March and October.
The months of greatest frequency are May and July. There
are exceptional instances in a long series of years where tor-
nadoes have been reported in every month of the year. They
may, and sometimes do, occur in some of the Southern States
during the winter and spring months. Taking the whole
United States together and averaging the dates of occurrence
for a long series of years (over 200) it is found that the
region of greatest frequency embraces the States of Kansas,
Illinois, Missouri, and Iowa. Of all the States in the
Union, Kansas and Missouri rank the highest in regard to
frequency.

HURRICANES.

Although it seems hardly necessary to'define the hurricane,
it will perhaps be well to state that as here considered it means a
straight wind of extraordinary velocity. It may, and frequently
does, occur without the accompaniment of any precipitation.
On the summit of Mount Washington, White Mountains,
New Hampshire, a measured velocity of nearly two hundred

miles per hour has been recorded. On the summit of Pike s
Peak, Rocky Mountains, Colorado, a measured velocity has
several times exceeded one hundred miles per hour. On the
coast of the Carolinas maximum measured velocities have
ranged from seventy-five to one hundred and sixty miles
per hour. In the Eastern Rocky Mountain Slope and in
the Lake Region measured velocities are sometimes re-
corded ranging between sixty and eighty miles per hour.
This storm may be known as the Blizzard of the Northwest,
the Chinook of the Northern Plateau, the Norther" of the
Southern Slope and Texas, or the Simoon of the Desert.
Hurricanes may occur at any hour of the day or night and
in any month of the year. The most violent, however, take
place during the spring and autumn. The width of the path
of the storm is very irregular and may vary from many rods
to many miles. In either case the velocity at all points within
the storm's path is not necessarily the same ; in fact such a
condition never occurs. The duration of the storm is also
extremely variable, it may continue for only a few minutes or
for several hours, although in the latter case the maximum
velocity is not maintained throughout the entire period;
on the contrary, there are periods of recurrence alternating
with decided diminutions of the highest activity. There are
perhaps but few portions of the country altogether free from
the possibility of their occurrence. In the low table-lands of
mountainous regions, where most of the country is extremely
broken, the habitable portions are shielded from the power of
violent wind-storms. No surface currents can attain any
great velocity in such regions, although on the mountain
peaks and elevated plateaus dangerous hurricanes at times
prevail.

WHIRLWINDS.

In defining these disturbances it will be best perhaps to
recall the occurrence, on a warm, dry day, of the formation
of a dust-whirl as it suddenly bursts upon you in the open

street, fairly enveloping your body with fine particles of dirt,
straw, leaves, and the like. Whirlwinds suddenly start up
from some barren, sandy spot unduly exposed to the direct
rays of the sun. Over a small surface thus exposed the air
rapidly rarifies, and ascensional currents form which move
spirally inward and upward, carrying dust, leaves, straws, and
sometimes objects of considerable weight. The whirlwind's
path has a diameter of several feet (sometimes rods), and the
direction of its course of movement is decidedly irregular,
possibly moving toward any point in the compass. On the
sandy plains of Arizona, Southern California, and Nevada
these phenomena occur with great frequency during the sum-
mer months. Columns of whirling sand, sometimes several
in a group, move rapidly over the surface. A whirlwind is
harmless and generally of but a few moments' duration. In
comparing it with the tornado let it be borne in mind that the
whirlwind starts from the earth's surface, extends upward and
moves onward, not leaving the earth, being solely confined
to the region of surface currents, while the tornado forms near
the superior limit of the lower regions of the atmosphere and
between the upper and lower sets of currents, or the currents
prevailing in the upper and lower regions of the atmosphere ;
the former currents are indicated by the appearance of the fine
cirrus* clouds and the latter by the heavy cumulus formations.
From this lofty seat of origin the tornado-cloud gradually
descends to the earth s surface, increasing rapidly in size and
augmenting in power.

WATERSPOUTS.

These disturbances generally form at a considerable height
in the air, although at times they seem to ascend from the
water's surface ; that is to say, there is no visible agent in-
fluencing the ascension of the water, but of course in every

* Cirrus clouds are fibrous or woolly-looking. Cumulus clouds are convex masses,
piled one upon another. Stratus clouds are spread over the face of the sky evenly
or in horizontal layers. Nimbus is a name given to ordinary rain-clouds.

instance the causative power is from above and in the latter
case near the water s surface. When I speak of the formation
of the waterspout at a considerable height in the air, I mean
that the embodiment of the whirl, or the revolving current of
air, first appears as a dark cloud of minutely divided particles
of water, the result of rapid condensation, of course in the
air and therefore above the water. The swift passage of the
air in a spirally upward motion over the surface of the water
raises it in the form of spray and carries it upward in the
center of the whirling cloud, which then presents the appear-
ance of a densely opaque body and conveys an impression
to the eye of the observer, that a huge column of water is
ascending in the form of a long spout, widening gradually
toward the top. There are instances, however, where the
force manifested is sufficient to raise a considerable quantity
of water several hundred feet in the air. Waterspouts form
during periods of excessive heat, generally in the afternoon
and at or near the hottest part of the day. In the temperate
zone they only occur during summer months. They are of
most frequent occurrence in the region of calms between the
tropics, but are not altogether strange sights in the Gulf of
Mexico and along the gulf stream south of parallel 40° N.
In regard to motions they possess both a rotary and pro-
gressive action, but in neither do they manifest a perma-
nency of direction. Waterspouts cannot be considered as
altogether harmless, for there are instances where vessels have
been wrecked by them.

HAILSTORMS

Are peculiar atmospheric disturbances which, in regard to
the dimensions of their paths, are next to the tornado the
most circumscribed of all storms save the whirlwind. They
are characterized by a strange cloud formation and a peculiar-
ity of precipitation unlike any other phenomena in the cate-
gory of storms. The cloud from which the hail falls is bas-

ket-shaped, with a dark and portentous exterior, a ragged and
ominous-looking opening at the bottom, and within a whirl-
ing conglomeration of snow-flakes, pellets of snow and ice,
partly formed and perfect hailstones, the latter of an almost
infinite variety of shapes. The hail-cloud forms between the
currents of the upper and lower regions of the atmosphere
and moves forward in the plane of these currents, either
within or just above the upper limit of the lower atmospheric
regions, where it finally disappears and the deposition of hail
ceases. The path of the storm, as indicated by the distribution
of the hailstones, is at times very narrow, although the range of
width is decidedly inconstant, varying from one to fifteen miles.
The hailstorm travels quite rapidly, from thirty to fifty miles per
hour, and the length of its path is even more variable than
the diameter, ranging as it does from ten miles to two hundred
or more. The direction of the course pursued by the storm
is always from some point west to some point east. It may
be from northwest to southeast or from southwest to northeast.
Hailstorms may occur at any time of the day or night, although
they are most frequent in the afternoon, just after or near the
hottest part of the day. They are most prevalent in that
region of country embraced between the parallels of 30° and
50° N. South of parallel 30° N. hailstorms are of rare oc-
currence at the level of the sea, but at the height of one or
two hundred feet they occur more frequently, and in the
mountains of British India they are very common, the hail-
stones being usually of large size. Hailstorms are not neces-
sarily confined to the land areas, but may and frequently do
occur over large and small bodies of water

THUNDER-STORMS.

These phenomena are atmospheric disturbances of great
variability of extent and power. They are always accompanied
by such manifestations of the presence of electricity as are
ordinarily termed thunder and lightning, the former being

entirely consequent upon the existence of the latter. Thun-
der is but the reverberation of the concussion produced by
the inconceivably rapid propulsion through the air of that
physical element we are pleased to term electricity. Thunder-
storms may be a few miles or several hundred in extent, and
their length of duration is quite as uncertain, viz. : from a few
hours to one or more days. There is no regular time of day
for their occurrence, although they are perhaps more fre-
quent in the afternoon. However, they may occur at any
time during the day or night. As to the season of year, sum-
mer is the period of greatest prevalency. There is no month
of the year entirely free from them. Whether the precipita-
tion be rain or snow the presence of electricity has still been
manifested in the usual form. With the former character of
condensation of vapor the evidence of electricity is . most
common, while with the latter it is the rare exception. As re-
gards geographical distribution, thunder-storms are most fre-
quent between the equator and parallel 40° N., and from thence
to parallel 70° N. the average frequency diminishes with
considerable rapidity. In the vicinity of parallel 80° N. it
is believed they never occur, although this in the main is
mere supposition. There are certain portions of the United
States where thunder-storms are unusually frequent as com-
pared with other parts. They seldom appear in the Pacific
Coast States, especially California, and are most frequent and
violent in the Eastern Rocky Mountain Slope, the Lower
Missouri Valley, and in the Lake Region.

Having briefly outlined the characteristics of the various
classes of storms, we will now proceed to consider more in
detail the most important (at least in certain respects) of
all atmospheric disturbances. At this stage of our inquiry in
regard to the character and classes of storms, I presume it
will be admitted, that no two of the several storms defined, at
least appear to be alike. There are, however, points of re-
semblance, but in some these features are stronger than in

others. As each is studied more carefully, the essential
points of difference will be more clearly contrasted. It is
not within the province of this book to discuss at length the
points of difference or harmony, nor to enter into an intricate
analysis of meteorological phenomena and the multiform op-
erations of atmospheric changes attending the origin, devel-
opment, and complete formation of these disturbances. On
the contrary, it is simply desired to present a brief but com-
prehensive resume of the leading features of storms, as known
at least in the United States, if not in North America, and in
particular to present rather a minute consideration of the
peculiarities of tornadoes, with a view to place at the disposal
of the people most interested^ the facts and practical results of
past and present investigations of this most terrible and yet
most wonderful and interesting of storms, the dreaded tornado.

THE TORNADO.

What is a tornado ? In defining this storm it would seem
almost a necessity to rehearse its long line of striking charac-
teristics, but this in the common acceptation of the term
would not strictly be a definition. For the sake of brevity,
we will state that the tornado is that form of atmospheric dis-
turbance which takes the outward, visible fashion or figure of
a funnel-shaped cloud, revolving about a vertical axis from
right to left* with an inconceivably rapid movement and an
immensity of power almost beyond calculation.

Conditions of Formation. — These may be divided into
classes. First, those within the reach of and which may be
known or investigated by an isolated observer. Second, those
conditions only to be witnessed and analyzed by the intelligent
and practiced eye of the student of the weather map. To the
single observer, located mayhap at his farm home, the work-
shop, or the store, there are important atmospheric conditions
which he may carefully watch and study with profit, viz. : the

* As you would turn a nut onto a bolt, point downward.

gradual setting in and prolonged movement of the air from ;

the north and south points ; the gradual but continued fall j
of the thermometer with a prevalence of the northerly currents,

or a rise with the predominance of the southerly. If the north- ;

erly currents are the prevailing air-movements at your place \

of observation, the atmospheric disturbance is forming to the |

southward, but if the prevailing air-currents are from the ;
south the storm is forming to the northward of your location.

Carefully study cloud development, color as well as form, also ;

manner and direction of approach. The approach of the cirrus ]

cloud (perhaps at a height of six to eight miles) from the \

southwest is very significant, and is the first evidence of the i
gradual but certain advance of the upper southwest current,

which eventually plays so important a part in the development ^

of the tornado-cloud. Clouds are but the embodiment of air- \

currents, yet they are full of meaning. A study of the upper j

currents of the atmosphere would be impossible without their j

manifestations, and that, too, in a variety of forms. Without |

cloud formation, the face of the sky would become a blank, j

and intelligent reasoning thereof a superhuman task, \

Wind direction, temperature, and clouds are the proper j

subjects of observation and thought by the isolated observer. \

The barometer is of little if any importance in this line of in- \

quiry. If you cannot compare your barometric observations ;

with those taken at near or distant points and at the same .,'

moment of actual time, they are of no practical moment, \

even though your instrument is a standard one and your cor- \

rections for temperature and elevation carefully applied. The j

storm you are watching for (the tornado) is an extremely ■

local affair, whereas the barometer indicates general changes, \

Note. — Photographs of tornadoes and tornado-clouds are rare. We "^^

have the reproductions of three which are claimed to be instantaneous ;

photographs, but the majority of our cloud illustrations are sketches \

from memory, most of them by persons not artists, and, while the col- 3

lection is the most varied and perhaps the most correct ever published, 1

we do not claim for it any higher merit than these facts will justify. 1

affecting a large extent of country. Your instrument, if a
standard, does not lack possession of the delicate sensitive-
ness requisite for all the purposes of its construction, but if it
were placed in the immediate track of the tornado-cloud, it
would not indicate its presence until the crash of the storm
was upon the instrument, when of course it would be too
late. Barometrical observations appear to advantage and are
absolutely necessary to a successful consideration of the mete-
orological conditions of tornadoes from the standpoint of the
weather map. From this panoramic view of the situation a
vast extent of country can be most carefully watched from
hour to hour, for days, weeks, or months. Atmospheric con-
ditions on opposite sides of the probable course of the storm
can be watched from their inception, and any relation easily
detected and analyzed. From a study of the weather-map it
has been found that the formation of what is termed a bar-
ometric trough or elongated area of low pressure (where the
barometer stands below the normal for that region at the
hour of observation) precedes the occurrence of tornadoes in
the Lower Missouri Valley or adjoining States to the south
and east. This low-pressure area assumes the form of an
ellipse and generally extends from southwest to northeast be-
tween northern Texas and the Upper Lake Region. Such a
depression may lie between the Central Mississippi Valley and
the Lower Lake Region, trending northeastward just south of
Michigan and over the Ohio Valley. The major axis * of
either of these depressions is easily estimated, while the minor
axis may be stated as generally varying from three to five
hundred miles. To the north of the major axis, even to a
distance of several hundred miles, the winds are found to
proceed from any or all points between northeast and north-
west with comparatively low temperatures, accompanied some-
times by a cold rain or even snow. South of the major axis,
and generally to a greater distance, the winds come from

* See chart No. 2, facing page 100 ; also illustrations on page 102.

any or all points between southeast and southwest, accom-
panied by comparatively high temperatures, high humidity,
and often dashes of quite heavy rain.

As these conditions continue to prevail there is a growing
contrast of temperature to the north and south of the major
axis, owing to the long-continued movement of the atmos-
phere from opposite directions, such movement eventually af-
fecting the disposition of air in the warmer regions of the
extreme south and likewise the colder regions of the extreme
north. The contrast of temperature now naturally increases
with marked rapidity, and the formation of clouds com-
mences in earnest. Huge masses of dark and portentous
appearance bank up in the northwest and southwest with
amazing rapidity, and soon the scene becomes one of awful
grandeur. The struggle for mastery in the opposing cur-
rents is thus indicated by the gathering cloud formations.
The condensation of vapor from the extremely humid south-
erly currents by contact with the augmenting cold of their
struggling opponents continues. It increases rapidly. Fi-
nally, when resistance to the unstable equilibrium can no
longer be maintained (controlled by the rate of temperature
change and rapidity of condensation), the opposing forces are,
as it were, broken asunder, followed by the upward rush of
huge volumes of air. The outward indication of this event
is first shown in the whirling, dashing clouds over the broken
surface of the heavy bank of condensed vapor, forming the
background. A scene not easily depicted or realized by one
who has not witnessed it, but never to be effaced from the
memory of the actual observer. There is an awful terror in
the majesty of the power here represented, and in the unnatu
ral movement of the clouds, which affects animals as well as
human beings. The next stage in the further development
of this atmospheric disturbance is the gradual descent of the
funnel-shaped cloud from a point apparently just beneath
the position of the enactment of the first scene. The tornado

is now before us, not fully developed, but soon to acquire
that condition when the terrible violence of its power will
make the earth tremble, animals terror-stricken, and men's
hearts quake with fear.

PREMONITORY SIGNS.

On the day of the storm, and for several hours previous
to the appearance of the tornado-cloud, the indications of its
probable formation and approach are within the comprehen-
sion of any ordinary observer and can readily be detected by
him. A sultry, oppressive condition of the atmosphere is
thus described by various observers as follows : "1 really
experienced a sickly sensation under the influence of the
sun's rays." I was compelled to stop work on account of
the peculiar exhaustion experienced from physical exertion."
*'It seemed as if the lightest garments that I could put on
were a burden to me." ''There was not a breath of air
stirring. " * ' The air at times came in puffs as from a heated
furnace." " I felt a want of breath, the air frequently appear-
ing too rarified to breathe freely." "I was starded at the
sudden and continued rise in the thermometer, especially at
this season of the year." *' In the forenoon I actually wore
an overcoat, but shortly after dinner I put on my straw hat
and worked in my shirt sleeves." I noticed a remarkable
change in the temperature, many of the neighbors spoke
about it and said that there was a peculiar feeling about the
heat, something they had not before experienced in years."
* ' It was terribly oppressive ; it seemed as if the atmosphere
was unusually heavy and pressing down on me with a great
weight."

These citations clearly indicate the character of this pecu-
liar sultriness. Other signs equally important and reliable
may be found in the development and peculiar formation
of the clouds in the western horizon. Sometimes these
peculiar clouds extend from the southwest through the west

by the north to the northeast. More frequently, however,
they form in the northwest and southwest, sometimes com-
mencing, first in the former quarter and then again in the
latter, but in either case they are equally significant. The
marked peculiarity of the clouds is found to occur not only
in the forin but in the color and character of development.

The sudden appearance of ominous clouds, first in the
southwest and then almost immediately in the northwest or
northeast (perhaps the reverse in the order of their appearance),
generally attracts the attention of the most casual observer,
and frequently overcomes him with astonishment. In almost
all cases these premonitory clouds are unlike any ordinary
and usual formation. If they are light, their appearance re-
sembles smoke issuing from a burning building or straw-
stack, rolling upward in fantastic shapes to great heights.
Again, like a fine mist or quite white, like fog or steam.
Some persons describe these light clouds as at times appar-
ently irridescent or glowing as if from their irregular surfaces
a pale, whitish light was cast.

The dark clouds at times present a deep, greenish hue,
which forebodes the greatest evil and leaves one to imagine
quite freely of dire possibilities. Again, they appear jet black
from center to circumference, or, in a change of form, this
deep-set color may only appear at the center, gradually dimin-
ishing in intensity as the outer edges of the cloud or bank of
clouds are approached. Sometimes these dark clouds, instead

Note. — The following three pictures are of the great tornado at
Ercildoun, Chester County, Penn., July i, 1877, and are from very
rough and imperfect sketches. The storm formed about 2:30 p. M. and
passed in a direction nearly due east for about twenty miles, injuring
many people and destroying over $40,000 of property. Width of track,
1 50 to 300 feet. Diameter of tornado-cloud, 50 to 75 feet. It is de-
scribed as having very closely resembled a balloon, although the
sketches do not disclose that fact. A balloon-shaped cloud is repre-
sented on another page as having appeared near North Vernon, Ind.,
in 1883.

of appearing in solid and heavy masses, roll up lightly, but
still intensely black, like the smoke from an engine or loco-
motive burning soft coal. They have been described as of a
purple or bluish tinge, or at times possessed of a strange
lividness. Frequently dark green, again an inky blackness
that fairly startles you with its intensity. Many observers are
at a loss for words in which to give an adequate description
of the terrible scenes and simply say : ''They were the worst-
looking clouds I ever saw, perfectly awful/' Said one
observer, ''The clouds seemed to be boiling up like muddy

Tornado at Ercildoun, Pa., July 1, 1877. First appearance. See note on
page 26 for description.

water, the upper surface of the cloud reminding me of the
incessant eddies or whirls seen in the muddiest portions of
the Missouri River." Other observers as follows : "I saw two
whirling circles of lightish gray clouds in the west ; they
were acting independently of each other and moved slowly
inward toward each other from opposite directions. The
clouds were very low, seemed to be on the earth, the wind

in contrary directions across the face of the western sky
and surrounding clouds in great confusion/' ''Observed
clouds moving in all directions, some of a dark green color,
others white as steam/' ''The lower end of the cloud was
very white, like fog." "I saw a great smoke, and supposed at
first it was a fire. " "I saw a terrible cloud of a dark
purplish color." *' There was a peculiar and terrifying look
to the clouds." " I saw a green-looking cloud in the north-
west, surrounded by others not so deep-set in color. Under
the cloud from the southwest, there came a large number of
little thunder-heads, some very dark but others as white as
steam. They seemed to be separated and running very low.
I never saw clouds so low before. Pretty soon they began
to go in all directions, some up, some down, right and left,
backwards and forwards. I next saw a cloud that looked
even all over in color and very white, the edges pretty even.
It moved remarkably steady and seemed to be right under
the edge of the cloud from the southwest." "The clouds
looked as if a mosquito-net had been spread out over the sky."
" I saw clouds tumbling over and over in terrible confusion."
"I noticed a strange action in the clouds and saw a cloud
rolling on the ground coming from the southwest." "The
ground was covered with white, steamy-looking clouds that
prevented one from seeing any distance." "Two clouds,
one from the northwest and the other from the southwest
seemed to meet, and after meeting passed still lower. Above
their place of meeting black smoke appeared in very pecu-
liar shape." " The air presented a very peculiar appearance,
it seemed to be in different-shaded strata and quite marked.
' ' At the bottom of the cloud a hazy appearance rose up,
obstructing the view." "Two clouds came together, one
from the southwest and the other from the northwest ; the
latter was the highest, and the former the heaviest and looked
the worst." " A heavy cloud spread out before us to a width
of about six hundred feet, and as black as night. "

The peculiar action of the clouds while they are forming is
another interesting and significant feature which should be
carefully watched. Under ordinary circumstances clouds
form, move about, and disappear without causing the slightest
remark, or perhaps thought, from the casual or even the
interested observer. In the event of a thunder-storm or hail-
storm the movement and disposition of the clouds are not
looked upon with fear or as possessed of power to create
great havoc, but on the occasion of a tornado the formation
and movement of the clouds strike most persons almost

Tornado at Ercildoun, Pa., July 1, 1877. Later appearance. See note on
page 26 for description.

dumb with fear; there seems to be some strange connection
between the almost .simultaneous appearance of clouds in
the southwest and northwest, possessing as they do such
unusually threatening forms.

As they approach from opposite directions they are sud-
denly thrown into the greatest confusion; breaking up, as it
were, into small portions, which dash pell-mell over each other
and in every direction ; now darting toward the earth,

now rushing upward to considerable heights like sky-
rockets, or at moderate elevations rolling over each other
in a well-developed whirl. An observer, in describing the
approach of the clouds from the southwest and northwest,
stated that they ''came together with a terrific crash, as if
thrown from the mouths of cannons. " Generally, following
closely upon the existence of this condition, the funnel-shaped
tornado-cloud appears against the western sky, moving
boldly to the front from without this confused mass of flying
clouds. As the tornado-cloud advances these scuds continue
to play about its top and sides, constituting a characteristic
feature of the scene.

Another and invariable sign of the tornado's approach is a
heavy, roaring noise, which augments in intensity as the tor-
nado-cloud advances. This roaring is compared to the pas-
sage of a heavily loaded freight train moving over a bridge
or through a deep pass or tunnel. To the roaring of a rail-
road train such as is heard on damp mornings when the
sound is very clear and loud. The sound coming from the
rapid movement of a large number of empty box cars is ac-
counted rather peculiar and quite noticeable. At times the roar-
ing has been so violent that persons have compared it to the
simultaneous ''rush of 10,000 trains of cars.'' Of course,
there is no importance to be attached to the exact number
here given, it being used in a figurative sense and is quite
likely exaggerated. Again, the roaring is likened to the
low rumbling of distant thunder. The varying intensity of
the roar as here represented is, in the main, due to the lack
of uniformity in the positions of the yarious observers with
respect to the advancing tornado-cloud. Those situated
nearest the cloud, other things being equal, experience the
loudest roar, while to those at greater distances the noise is
proportionally weaker. In any event, however, the noise
is sufficiently peculiar and distinct to create alarm, and as a
means of warnijig should not be overlooked under any pretext.

How TO Benefit by Signs. — In order to be prepared for
the possible appearance of a tornado, so far at least as the
above indications are concerned, let every person situated
in those regions of country where the tornado is of yearly
occurrence commence (to-day is none too soon) to carefully
observe and record the daily changes in the face of the sky,
the variations of temperature, the direction of the wind and

Tornado at Ercildouii, Pa., July, 1, 1877. Last appearance. See note on
page 26 for description.

the character and development of clouds. We do not mean
that any person should devote all or most of his time to this
work of observation, and possibly not even all of his spare
time. For the sake of regularity and uniformity we will
suggest certain hours for regular work of this nature, viz. : 7
A. M. and 2 and 9 p. m. These hours are not altogether
arbitrary, but there is a reasonable amount of prudence in
their selection, looking to a proper and successful use of the
results of your labor.

Should the violence of a storm be unusually marked during
either the hours of the forenoon or afternoon, or even in the

night, it would be advisable to increase the number of hours
for observation and record, possibly making them every hour
or half hour, or even at shorter intervals, as the importance
of the case demands. By this means of frequent observa-
tion every feature of the storm would become the sub-
ject of inquiry and the most important results would be
attained. For purposes of investigation of this class of
storms your observations need not continue throughout the
entire year, at least in the Northern and Western States,
although such a length of record would by no means fall
amiss of great value. Yearly records will pay. However,
observations should commence without fail by the istof April,
and continue unremittingly until at least the last of Septem-
ber. Observations through the autumn can be maintained
with profit. It will be a valuable adjunct to this work of
regular-hour records if a summary of miscellaneous phe-
nomena is kept Enter the dates of occurrence and im-
portant particulars of such phenomena as auroras, mirage,
meteors, lunar and solar halos, prairie and forest fires; the
migration of birds and insects; the leafing and blossoming
of trees, flowers, and shrubs; droughts, excessive rainfalls,
earthquakes, zodiacal light, frosts and the formation of ice.
The great importance of systematic observation and record
is urged with much earnestness, particularly in the tornado
districts and during the tornado season, but further detail
is omitted in this place and the student and volunteer
observer are warmly recommended to examine the tornado cir-
cular of the Signal Service, which is printed in full at the end
of the book. It contains 234 questions and suggestions,
under eighteen different headings, and constitutes the most
complete, as well as the most compact, scheme of instruction
ever compiled for the purpose.

Character of Tornado-Cloud and Attending Motions. —
The tornado-cloud is, genei;ally speaking, funnel-shaped,
that is to say, it tapers from the top downward, not always

in\ the same degree with every appearance of the cloud,
bat the lower end of it (the part nearest the eanh) is in-
vairiably the smallest. Whatever the inclination of the
central axis of the cloud to the vertical or plumb line, the lowest
erid is the narrov/est and nearest the earth. As seen in differ-
ent positions and stages of development by various observers,
Icpcated differently, the tornado-cloud has been called : '*bal-
l())on-shaped * ' basket-shaped * ' egg-shaped * * trailing
oji the ground like the tail of an enormous kite of bulb-
ejus form;" *Mike an elephant's trunk,'*' etc., etc. In the
majority of instances, however, observers describe the cloud
as appearing like an upright funneL When the tip end of

Tornado-cloud ivhich passed near Garnett, Kansas, at 5:30 r. tt, April 26,
1884. From au iiistautaueous pUotograpIu

the cloud reaches the earth, the violence of its whirl creates a
powerful suction over a small portion of the surface, upon
which there is immediately formed a peculiar cloud of dust,
and finely divided debris, around which play small gatl(ier-
ings of condensed vapor. To all appearances now, the
tornado-cloud has two heads, one on the surface of ihe
earth and the other in the sky, the bodies of each joimVig
in mid-air and tapering both ways with the smallest diamdter
at their junction. In other words, the cloud now assumes
the shape of an hour-glass and the lower portion, or tjiat
assuming the form of an inverted funnel, displays an ex-
traordinary violence. The extreme fury and the tremendous
power of the tornado-cloud are now experienced, and nojth-^
ing is able to stay the awful force of its onward march. This
last and most fatal form of the tornado-cloud is fortunately not
a constant feature of Che storm. The tornado-cloud is con-
stantly changing from the hour-glass form to that of the
upright funnel or some other intermediate shape previously
referred to.

The various gradations of form, not any of which, however,
affect the stereotyped relation between the size of top and
bottom, number some twenty-five or thirty, so far as I have
been able to gather information upon this point. These
variations of form are quite important in a critical study of
the tornado. They depend upon the peculiar movements
of the whirling currents of air within and about the cloud
vortex, the direction of the currents being outlined to the
eye by the singular disposition of the rapidly condensing
masses of vapor. The characteristic motions of the tornado-
cloud number four, and are described as follows : —

No. L is called the whirling or gyratory motion of the tor-
nado-cloud, which is invariably from right to left, or against
the course of the sun. From the peculiar character of the
formation of the tornado-cloud, this motion is in all prob-
ability the first evidence of the existence of the cloud, and

shotald therefore be .placed first in order of consideration.
Above all other motions, this is attended with the greatest
violjence, and its velocity of movement is far in excess of any of
the others. This gyratory motion forms what is termed the
vortex of the tornado-cloud, within which the velocity of the
centripetal currents of air is almost beyond conception.
Malny efforts have been made, but most of them altogether
fruitless, to estimate the rate of progress of these currents, and
velocities ranging from roo to 800, and even 1,000 miles
per hour, have been deduced; the two latter are the ex-
treiiies that have been ventured upon and of course are not
reliable, while in the majority of instances more trustworthy
determinations have ranged between 100 and 500 miles per
hour. Theoretical velocities of over 2,000 miles per hour,
based upon certain assumed atmospheric conditions, have
been deduced. Such velocities are mathematically possible,
but not meteorologically probable.

The uncertainty in computing the velocity of centripetal
currents arises from the difficulty attending the acquirement
of the requisite data. In all carefully conducted investiga-
tions heretofore made, there has unfortunately occurred such
a long interval between the happening of the storm and the
arrival of the person authorized to commence the work, that
valuable and satisfactory results in this direction were pre-
cluded. It is always of prime importance to ascertain
definitely what portion of a building or other object was first
struck by the wind in order to determine the configuration
and inclination of the exposed surface. As a rule such
examination is rendered next to impossible by the rapidity
with which devastated districts recover from the violence of
the storm. This fact is a most praiseworthy and well-
deserved commentary' on the exemplary industry and deter-
mined spirit of the people of the Lower Missouri Valley,
With the gyratory motion of the tornado-cloud, objects are
drawn inward to the center of the storm and then carried

violently upward by a spirally inward and upward motion
which fairly crushes and grinds into pieces buildings, trees,
and whatever else falls in the line of the advancing cloud.
The spirally upward motion throws the ascending debris iri a
circular manner outward at the top of the tornado-cloud.
This debris, when beyond the central whirl of the cloud, fillls
to the earth, but in such a manner and so disposed as to
indicate the character of the force which acted upon it

Tornado near Redstone, DaTl.sonCo., xvakota^ Aug. 28, 1884. From asketcli
by J. H. Nott. See o^>i>osite pafre. These two pictures of the same storm, made
20 miles apart in aiMoiiiing counties hy different pei-sons having no knowledge
of each other, are valuable conhnnatious ol one another.

No. II. is called the progressive motion of the tornado-
cloud, the motion which determines the cloud's track from
one point to another. The rate of progressive velocity ranks
next in order to the velocity of motion No. L, although it is
at all times far below the high degree of the latter.

The rate of progress of the tornado-cloud is subject to
great variability throughout the path of any one storm, al-
though on the average tornado-clouds possess a moderately
uniform velocity of progression. Some observers have indi-
cated the movement by the following expressions: ''All in
an instant" ''Gone in a moment'' "Quicker than

chonght'^ " Without a moment's warning/* It moved no
fester than a horse gently galloping." ' * I just saw what it was
and then all was over." Before I had time to turn about
in my tracks it flashed by me/' It seemed to remain almost
motionless, as if held to the ground by some mysterious force."
**I shuddered, held my breath, and the monster had van-
ished." *' It seemed to move no fester than I could run."

Toirodo clouaaaseeiiatllowarcL Miner Co., lKikota» Ang. 28.1884. Photo-
graphed by F. N. RohiBSon. The clond passed 22 niUea west of aim in a soiith-
easferly direction, remaining in sight over two boui-s. Several people were
lulIod» and ali property in the path was destroyeiL

These estimations of velocity are not to be taken alto-
gether literally. The circumstances under which the im-
pressions were received must be considered, viz.: undue
excitement or abject terror. However, the comparative re-
sults are important, and to a certain extent reliable.
Through them, the reader will at least not be led astray in his
conceptions of the awful grandeur of the panorama, or fall
into the fatal mistake of encouraging a belief that the tor-
nado is not what the united experience of all observ'ers has
portrayed it.

Such data will not answer, however, to figure on very
closely, but the items, average diameter of cloud, actual time
(local or standard), and measured distances, must be care^
fully obtained before an approach to accurate calculations
can be secured. Reliable data are very difficult to obtain,
especially time. This fact should be thoroughly appre-
ciated by observers and every reasonable effort made by them
to examine their clocks or watches upon the approach 'and
passage of the tornado-cloud. Generally speaking, it is a
good habit to form, of jotting down in some place of rfeady
reference the hour, day, month, and year of nolable
eventSe In regard to this matter of time, so far as past de-
terminations can be valued, the progressive velocity of the
tornado-cloud is variously estimated at from twenty-five to
seventy miles per houn The former is perhaps too low and
the latter quite likely too high, and although in both in-
stances they represent the extremes, yet either of the above
velocities may have existed for short intervals. The general
average is probably about forty miles per hour.

No, III. is termed the rising and falling motion of the
tornado-cloud, the character of which finds definition in the
following expressions from various witnesses: *'The top of
the cloud seemed to pop up and down, and then to rush for-
ward." **It bounded over the ground like a ball." It
was the strangest jumping and flopping object I ever saw."

At times it seemed to lash the earth in terrific fury with its
huge tail." ''It came along, popping up and down in a
most fantastic way." ''Rising up like the uncoiling of a
huge rope, it cut loose from the earth and passed over us
with a horribly whizzing sound. " ' ' Ever and anon it would
shoot directly upward from the earth, sometimes with great
rapidity, and then again quite slowly, each time dashing to
the surface with apparently renewed vigor." It is perhaps
clearly seen that this is a distinct motion with striking pecu-
liarities which define its character. Sometimes, upon the

liftilig of the tornado-cloud from the earth, it does not again
desrt:end for a distance of several miles, at times making the
retifm movement or descension twenty or thirty miles distant,
the( intervening space proving a complete blank in its track.
More frequently, however, the!5e gaps are from one to five
miles in length.

While the tornado-cloud is traversing the atmosphere at
some considerable distance above the earth, it may reach
down so low as to just skim over the tops of the highest
trees; descend to a level with the roofs of buildings, simply
scaling off the shingles in spots or entirely on one side, leav-
ing the roof-boards and rafters unmoved; removing the tops
of chimneys ; taking out all the fans in the wheel of a wind-
mill and leaving every portion (even the tail) of the re-
mainder of the mill unharmed ; take off the cornice without
disturbing the remainder of the roof; removing simply the
top board of a five-board fence, or one or two of the top
rails of an ordinary rail fence. The tornado-cloud may,
however, remain at a perfectly safe distance throughout its
aerial course, and where it may be seen at a great height,
moving solitary and alone, like a huge balloon. While in
this condition it has not a few times been unwittingly taken
for the latter object, but the mystery and sensation were en-
tirely dispelled when the news came in from the surrounding
country of the frightful power of this now silent monster.

There is still another condition, which the fearful aeronaut
may assume in his flighty movements. Upon rising fiom
the earth and passing through a few uncertain struggles, ap-
parently to decide as to whether the final direction shall be
up or down, the tornado-cloud is ultimately lost sight of in
the surrounding clouds, and re-appears suddenly again at its
point of descension, or perhaps only to remain at a safe dis-
tance.

No. IV. is called the zigzag motion, or swaying from side
to side of the central line of cloud movement. This motion

is sometimes quite suddenly performed, but generally it is a
moderately slow movement and one that can be watched and
easily identified. It seems to occur most frequently just as
the tornado-cloud touches the earth in completing the last act
of motion No. III. In completing the extent of a single act
of this motion, the toniado-cloud will diverge about an equal
distance on either side of the central line of movement,
though these tangents to the major axis are not necessarily of
equal length.

At the commencement of this motion the tornado-cloud
always moves first to the left (N. N. E. ) and then to the right
(E. S. E.) forming an obtuse angle on the north side of the
major axis. On the return movement, the cloud may or may
not cross the major axis (to E, S. E.). If it does, it will then
form a similar obtuse angle on the south side of the major
axis. This zigzag movement, first from one side and then
from the other of the central line of progressive action, may
continue for several miles^ or it may cut short its existence
after the first few moves. The regularity of this peculiar ac-
tion appears to depend upon indraughts from the south side
of the major a^^is of violent currents of air, which frequently
advance (only from the south side) and give evidence of
their existence by swaths or narrow paths of destruction (al-
ternating with spaces of no damage) cut inward toward and
joining with the central line or track. The tornado-cloud
may, upon the return movement (whether executed upon the
north or south side of the major axis, it matters not), fail to
cross it, but upon reaching it, continue onward in the central
line of movement to the northeast

The distance traveled by the tornado-cloud in departing
from the major axis, * either to the north or south, is gener-
ally subject to considerable variability, ranging from forty or
fifty yards to nearly as many rods. While executing this zigzag
motion itvery frequently happens that the tornado-cloud simply
skims over the earth without manifesting its extreme violence.

Building Spots.— In regard to the matter of buildiings,
the question may be asked whether there is not some choice
in a building spot, with a view to safety from the viol ence
of the tornado-cloud. Many persons have thought that if
their house or barn was perched upon some high " divide,"
or on the brow of a steep decline, in fact upon any mai:ked
rise above the surrounding level, the tornado-cloud by reason
of some mysterious effort of clemency would rise from the
earth and pass over them. This is a careless and unreason-
able supposition when the facts are known. It does not
seem to occur to the mind of an observer that there is no
reason why the tornado-cloud should not follow the rolling
surface as well as the plain. The tornado-cloud pursues a
general course to the northeast without regard to the charac-
ter of the earth's surface, and if your buildings are in the
line of its destructive path, whether upon a hill, in a valley, or
within a ravine, they are subject to its violence. Western towns
as a rule are not built upon high * divides," but are more
frequently sheltered between neighboring hills. The same
may be said of farm buildings, it being the prevailing cus-
tom to select building spots along the low bottoms of a
stream for convenience to water and timber, and for protec-
tion from the continued heavy winds that break over the
open prairies.

From the above facts it will be seen that there is very little
opportunity offered the tornado-cloud to display its violence
on the hill-tops, even though it were so disposed. Repeated
investigations have shown that buildings were destroyed with
as great violence and completeness upon high lands as upon
low lands, but the largest number in valleys because of the
facts above cited. In many instances the funnel-cloud has
passed from one ridge to another, doing damage on both,
but skipping the intervening depression. Again, it has fol-
lowed high ' ^ divides " for several miles where they coincided
with its general course of movement. Ridges and valleys

are almost invariably crossed at right angles when their
courses are from northwest to southeast^

Electricity. — ^The rain and hail which sometimes pre-
cede and at other times follow the tornado-cloud, but always
accompany the heavy clouds which form in the north and
west, are not always but generally attended by lightning ;
somietimes most violent manifestations, and then again but
occasional flashes. The most terrific displays are reported
during the heavy precipitation which often occurs after the
tornado-cloud has passed, some ten to twenty minutes.
Very often its darting flash is observed in the dark clouds
which begin to rise above the western horizon an hour or
more before the storm. The relations of electricity to the
tornado are so fully and so conclusively set forth in the
''Scientific Resume," printed at pages 147, etc., that further
examination of that particular point is omitted here.

PROTECTION,

If you have a tornado-cave or a dug-out, get into it with
your family and your treasures before the storm reaches you ;
if you have no such means of retreat and cannot get away
from the storm, go into your cellar and get as close to the
west wall as possible, ne:ver go to the east side of a cellar or of
any other ihiclosed space in any building toward which the
tornado is approaching; always seek the west side, towards
THE STORM. Frequently life may be saved by timely flight
in the rig& direction, A tornado travels from southwest to
northeast stand facing it as it approaches ; if it is going
to the right of you, run to the left ; if it is going to the left of
you, run to the right ; never run towards the storm nor with it,

ALWAYS RUN TO THE NORTHWARD OR SOUTHWARD AT A RIGHT
ANGLE FROM IT, GIVING THE BENEFIT OF DOUBT IN FAVOR OF THE

NORTH. Read attentively the small print following for details
in regard to saving life, property, and live-stock.

Means of Protection. — First in regard to life. How can you save
your life or avoid injury ? In regard to this question much, if not
everything, depends upon the manner and in what direction you
7nove^ together with the distance of the tornado-cloud, its direction,
and the kind of motion prevailing at the instant you determine upon
changing your location.

We will now suppose the various conditions, and proceed to poi4t out
the necessary action in each instance. In all cases it is granted f(ir the
sake of convenience in illustration, that you are in front of or situated
directly in the line of the advancing tornado-cloud. Under thes(^ cir-
cumstances if No. II., or the progressive motion of the cloud is prevailing,

and your distance from it is, say, eighty rods or more, move directly
and with all possible dispatch to the north. Whenever this motion is
prevailing always run to the north, unless in so doing you would be
obliged to cross the entire path of the storm. A sharp glance to the

westward will tell yon whether you are about on the southern edge of
the probable path of the tornado-cloud, or more to the north. If in the
center or half-way between the center and the southern edge, your
chances are best in a direct course to the north. If further to the south,
move directly and very rapidly to the south, bearing slightly east. In
no event should you ever run directly to the east or northeast. Sup-
pose the tornado-cloud to be distant from you (W. or S.W.) eighty rods
and its progressive velocity sixty miles per hour, it would follow that
one mile is passed in sixty seconds, or eighty rods in fifteen seconds.
Assuming the average width of the destructive path of the tornado-
cloud to be forty rods and your position at the center of that path, it
will be seen that you have fifteen seconds in which to reach the outer
edge of the path to the north (a distance of twenty rods) before the
tornado-cloud could arrive at your location.

I have taken an extreme case in every particular. Most persons first
see the tornado-cloud at a much greater distance, from one to three
miles, sometimes five and ten miles -on the prairies. Of course, at the
unusual distance of five or ten miles you could not determine very sat-
isfactorily its probable course, especially with regard to your buildings
or the safety of your own location. Watching the approach of the
tornado -cloud closely at a distance of ten miles, and from that position
on and on in its eastward course until it came within a mile or so of your
point of observation, would give you sufficient opportunity to predict its
probable course in regard to your location. When that matter is set-
tled satisfactorily to your judgment, move immediately and without
further hesitation. If you wait until the tornado-cloud is distant one
mile, you have at least sixty seconds in which to run a distance of thirty
rods, supposing that you are obliged to cover more than half of the de-
structive path of the storm. In an average case you will probably
have between eighty and ninety seconds in which to run a distance of
twenty rods. In either case I am supposing that you are prepared in
every particular to move at the very instant of timely warning.
Further, I am supposing that you have been watching the weather of
the day and understand that a terrible storm is imminent There is,
under ordinary circumstances, no reason why you shoiild not be so in-
formed. A tornado- cloud does not come out of a clear sky, and there
are many and ample signs of its approach.

What has been said in regard to the directions in which persons
should move when the progressive motion is prevailing, will for all
practical purposes apply to motions Nos. I. and III. With respect to
motion No. IV. (the zigzag) the following preliminary remarks should
be most carefully considered. Remember that while possessed of this

motion the tornado-cloud crosses from one side of the central line of
movement or major axis to the other. That this peculiar motion most
frequently occurs just after the termination of the rising and falling mo-
tion (No. IIL), so that when you see the tornado-cloud descending to the
earth from one of its aerial flights you may expect (not absolutely) the
zigzag motion to follow. That the first departure of the tornado-cloud
from the major axis is to the left or on the north side of the path.
That all departures from the major axis, whether forward or return
movements of the tornado-cloud, are mvariably executed to the east-
ward. There is no backward movement to the west. That the
tornado-cloud never continues to move in the direction of any tangent
to the major axis, but in the event of any departure it ultimately re-
turns to the central line of movement. Having these points well in
mind, you are quite satisfactorily prepared to act when the exigency oc-
curs. When the departure of the tornado-cloud is to the left and your
position is at any point in the central line of movement (better near the
center of the path), move directly north with the utmost rapidity, even
if the cloud is at a long distance from you. Should ic chance that your
distance from the cloud is reduced to from twenty to forty rods, run in-
stantly to the south, bearing slightly west. This movement will take
you away from the forward and return action of the tornado-cloud.
Another case, suppose your position to be the same as just given, viz. :
at any point in the central line of movement, but that the tornado-
cloud had just crossed over that line to the southward. In this event
you should move instantly and directly to the north, bearing slightly
west. This movement will also, as in the case previously cited, take
you away from the forward and return action of the tornado-cloud.

How TO Act on its Formation. — The following remarks apply to
your manner of action when the evidences of the existence of the
tornado-cloud are undeniable. Suppose the actual tornado cloud is
not yet in sight, but other infallible signs (heretofore given) of its forma-
tion and probable approach from a point possibly below your horizon,
are present. Act immediately, judiciously, and with the utmost rapidity,
but never for one instant allow yourself to become excited or reckless
in anything. Take the situation as calmly as possible, knowing as you
ought (or probably will) the terrible power you have to deal with. Do
not, with an overweening sense of fancied security or an inclination to
a superstitious feeling that your life is mysteriously over-shadowed by a
peculiarly beneficent power, think and act leisurely about the matter of
self-protection. A tornado-cloud never sends forward a flag of truce
or even solicits the "right of way." There are certam indications
which we have heretofore spoken of that frequently, if not always,

manifest themselves from half an hour to two or three hours in advance
of the tornado-cloud.

Many foolhardy acts have been committed, perhaps through fear and
excitement or positive ignorance, which have resulted in death or dread-
ful injuries, because persons have tried to run in front of the tornado-
cloud, thinking they could outstrip it in such a race. Others have at-=
tempted to cross the path just ahead of the advancing cloud, feeling
that they could reach a safe distance on the opposite side before the
funnel-shaped monster passed. In one of our late storms a person es=
sayed this trip with two horses and a lumber wagon, confident that he
could at least rush his horses across the apparently narrow path of a
storm which seemed to progress within such circumscribed limits. Not
so. He was instantly killed, one of his horses dreadfully mangled, the
other seriously injured, and the wagon a total wreck. The work of an
instant. An ignorant, reckless rush into eternity.

Protection of Property, — What can be done to in any way lessen
the actual damage (present or prospective) to property, especially
buildings ? In the first place it is impossible to move your buildings
from the path of the advancing tornado-cloud. Secondly, it is impos-
sible to stop the tornado-cloud after it has started on its course of death
and destruction, or in any way prevent its formation. Thirdly, it is
impossible to construct any building strong enough to completely resist
the extraordinary violence of the tornado-cloud. To sum up, this is
all equivalent to saying that you can never expect to save your build-
ings. This is the truth as I comprehend it, and it is that to which all
thought upon the subject will sooner or later conform. It is advisable
that, under all circumstances, you should avoid any labor especially
directed to the construction of any building whatsoever, for the express
purpose of resisting the violence of the tornado-cloud. Build your
houses, bams, and stores as you would without the knowledge of a
tornado. Other things being equal, a frame building is better than a
brick oi stone one. The former will hold together longer, is more elas-
tic (if you will permit the term), and persons seeking refuge within its
walls are much less liable to injury. There has at times been evidence
to show that, of all frame buildings, those constructed with a hip-roof
and a story and a half in height were the best able to resist the vio-
lence of the tornado. But where there are cases reported of this class
of buildings^ being saved there are as many, if not more, where they
were destroyed precisely as any other frame building would have been
under similar circumstances.

It matters not how you construct or of what material, if your building
rises above the surface of the earth, which it must necessarily do, it

thereby offers obstruction to the advance of the tornado-cloud, and it
will go, either from the foundation, or into kindling-wood and a dis-
tracted mass of bricks and mortar, in spite of the propagation of any
theory on the possibilities of architectural skiU. In conclusion I would
finally say, that you must take every precaution to avoid or remove
from, rather than attempt to fight against or any way resist, the power
of this formidable adversary. The question now suggests itself, what
can be done ? That which remains to be done can be accomplished in
an unostentatious and quiet, but secure manner. Every man can and
should construct a tornado-cave at some suitable point, within a conve-
nient distance of his housCc If a person is situated within a town or
city, let him select some portion of his yard for the purpose, but if re=
siding in the country he will not be confined to narrow limits in the
selection of a desirable location. Where a person living in the village
has no yard, he must, if he has a cellar, construct a cellar tornado-cave
to be described further on. With respect to the tornado-cave, in no event
should the roof be other than level with the surface of the earth; in
fact it is highly desirable that the retreat should be so constructed that
the ordinary surface of the earth would form the roof or covering, and
that all preparation of the domicile proceed by way of excavations and
supports from beneath. As to location, the most important points are,
excavation of cave to the westward of house or other building; con-
venient distance ; a high, dry place, and possible opportunities to exca=
vate into the northern or eastern slope of a knoll or hill. In the latter
instance the entrance way would suffer less from the violence of the
storm, providing, perhaps, that it did not entirely envelop your re-
treat, for in that even t,] in the whirl of the flying debris, all sides
alike would be at the mercy of the winds. Having decided upon the
location, as regards your house or other buildings, sink a shaft, say,
four to six feet square, the entire depth of yom* tornado-cave. From
either the northern or eastern (better the former) wall of this shaft,
make the necessary preparations for purposes of ingress and egress.
On the west side of the shaft commence the excavation for the in-
closed retreat. The size of the room will of course depend upon how
much you may at any time wish to secure from injury. Better have the
excavation too large than not large enough. The slight difference in
the expense of time and labor may, perhaps, be the means of saving you
a great deal when you least expect it. The entire room should be be»
low the surface of the ground a distance of at least three feet, and the
overhanging roof of earth should be supported from beneath by heavy
timbers, to provide against any emergency, like the dashing of heavy
debus upon it or the tramping of horses and cattle.

In the event of a tornado your retreat (lornado-cave) may be entirely
buried beneath huge piles of debris. Everything mubt be made as se-
cure as possible. The entrance door should be made, either of sheet
iron or of the heaviest timbers and supported between casings of similar
strength of construction. Arrangements should be made to secure the
door by heavy fastenings. In order that ventilation may be provided-
for, a box spout, of hard wood or vitrified tile, squaring about eight
inches, can be let through the roof. The top of this spout must be
level with the surface of the ground and protected by iron gratings.
Ventilation may be provided for by openings through the upper por-
tion of the door, but these also should be protected by iron gratings.
The question of how to provide the most approved form of tornado-
cave, with every detail of cost, material, and method of construction, is
very fully considered a few pages further along.

If you are not possessed of the tornado-cave or cellar tornado-cave,
your best plan is to move from your house or wherever you may be at
the moment, as directed concerning the various motions of the tornado-
cloud. If not able to benefit by these directions, retreat instantly to your
cellar and place yourself, face forward, against the west walL This is
the best position in any cellar. If, for any reason,- you cannot get to the
west wall, take your position (the next best) face forward against the south
wall, but as near the southwest corner as possible. In these positions
the building, if removed from the foundation, will always be carried
above and over you, or if torn to pieces, the debris will be instantly re-
moved to the eastward. Under no circumstances^ whether in a building
or a cellar^ ever take a position in a northeast room, in a northeast cor-
ner, in an east room, or against an east wall. Remember that the tor-
nado-cloud invariably moves in a northeasterly direction. I have not
space here in which to relate to you, how many and in what manner,
persons have been instantly killed or terribly crippled, for no other rea-
son than that they ignorantly threw themselves within the very grasp
of the monster cloud. The lives of most, if not all, of the people de-
stroyed in tornadoes might have been saved by a clear understanding
and a strict adherence to the simple rules herein set forth.

The rule prohibiting movement to the northeast must be obeyed.
The northeast quarter is a fatal position, and I care not what you may
tell me about destruction to life or property in any other. If you can
get out of your house never remain in it or any other building that
is at all likely to be torn down or removed from its foundation. If
through some misfortune you are closely pressed by the advancing
cloud, never remain standing and attempt to weather the storm, but
throw yourself prone (face downward) upon the ground, head to the

east, and arms thrown over the head to protect it. If you should
chance to be near a large stone ur stump, or some heavy object low
down and firmly imbedded in the ground, take a position directly to
the east of it, lying prone upon the earth, head toward the object,
protecting the former with your folded arms. This advice is given in
the event of extreme exigencies where other and better opportunities
have been forfeited. It is better, if possible, never to trust yourself be-
hind or about any object located within the center of the storm's path ;
by all means not a tree or any object that rises some distance above the
surface of the ground. If forced to remam in your house and where
you have no cellar, always take a position against the west or south
wall (better the former) either prone (face downward) upon the floor or
standing with your back to the wall.

In any building always take your final position on the first or ground
floor. Never stand or lie in front of a door or window, or near a stove or
heavy piece of furniture. Make every effort to get into the west room,
and if possible before the onslaught remove therefrom all furniture, at
least from the western portion. Always shut tightly every window and
door in your house or other building in which you may be located at the
time of the storm. You should never let doors and windows remain
open during any violent storm. Never take refuge in a forest, in a
small grove of trees, in an orchard, or near a fence of any kind, unless
all these obstructions are entirely out of the line of the storm.

If possible, always open your buildings and let your stock out, driv-
ing them to the north. In this matter of caring for stock (which should
not be neglected if otherwise possible) always drive them from your
buildings to the (as a rule) northward. Try and perform this duty on
the first indications of the character of the storm, though not until you
have assured yourself of the probable course of the tornado-cloud. Of
course it is quite possible that the tornado- cloud may pass to the north
of your buildings; in that event your stock should be driven southward,
and vice versa*

PRIZE TORNADO-CAVE.

Through the courtesy of the Burlington Insurance Com-
pany, of Iowa, we are the first to publish the design of John
R. Church, architect, of Rochester, New York, which was the
one selected by the author (empowered by the Burlington
Company to adjudicate the claims of competitors and award
the prize) from 122 designs submitted in competition for the
$200 prize offered by that company.

These plans and specifications, and all that pertains to
them, are protected by special copyright, and are the property
of the Burlington Insurance Company.

DESIGN FOR A TORNADO-CAVE, BY JOHN R. CHURCH,
ARCHITECT, ROCHESTER, N. Y.

The general design of the cave is indicated by the accom-
panying drawings.

The cave is designed for two different methods of entrance.
In design A " the entrance is from the cellar of dwelling. In
design B " the plan is intended for a dwelling without cellar,
the entrance to cave is from a room in the rear part of dwell-
ing and through trap-door in floor.

The drawings indicate walls of stone 18 inches in thickness; it
is intended that they should be laid up in mortar of good quality
cement and clean, sharp sand. The excavation should be made
large enough to allow the walls to be pointed and plastered on
the outside with cement mortar, to prevent water from coming
through them. The walls should be started on a bed of cement
mortar i inch thick.

In a country where stone is more expensive than brick, an
8-inch brick wall can be substituted for the stone wall, plas-
tering the wall on the outside with cement mortar and laying the
brick in same kind of mortar.

The floor of the cave and passages to be paved with one course
of hard-burned" brick, these to be laid on a bed of cement

mortar 2 inches thick, and the joints to be thoroughly grouted
with cement.

The construction of the roof to be with iron beams and 8-inch
arches of " hard-burned" brick as shown, the brick to be laid
in cement mortar, top to be leveled up and sloped as indicated
with concrete, and the whole to be covered with a coating of
best roofing pitch ; this to be applied hot and the roof made
water-tight. Roof of the passage to be constructed in same way.

Iron beams indicated should be 6 incheS; 40 lbs. per yard,
with 4x6 inch angle-irons laid on the walls as shown - to pro-
vide skewbacks for the arches — angle irons to weigh 30 lbs. per
yard. The bolts to be i inch in diameter, and to be fixed as
indicated. Roof of the exit ''to be covered with flag-stone
6 inches thick.,

For ventilation two lines of 12-inch, salt-glazed, vitrified tile are
provided, these to connect with outer air as indicated, tile to
run up above the ground about 6 inches and to have cast-iron
grating in top.

The doors to be made of 2-inch matched plank, hung with
strap hinges, battened, and provided with bolts, latches, etc.

An exit to open air is provided in addition to the entrance to
cave from dwelling ; this can also be used for an entrance if
desired

SPECIFICATION

Of materials and labor required in the construction of a *' tornado-
cave " for Mr. to be located on the west side of his dwelling,

situated , in accordance with accompanying drawings prepared

by John R. Church, architect, 54 Osburn House Block, Rochester, N. Y.

DIMENSIONS.

The size of the cave to be seven feet by twelve feet inside, and the
height to be six feet six inches in the clear, passages, etc., all to be as
shown on the drawings, which consist of —

(i.) Plan of the cave at ground.

(2. ) Plan of cave below ground.

(3.) Four sections of cave on different lines.

(4. ) Perspective sketch of entrance.

(5.) Perspective sketch of interior. Drawings have the scale indi-
cated on them.

EXCAVATION.

Excavate for the cave, the passage from cellar or house, and for the
exit-passage, all as shown on the drawings. The excavation to be
made large — at least eighteen inches outside of the walls on all sides —
so that the walls can be plastered on the outside.

The excavation to be carried down to seven feet below the surface of
the ground, as indicated on the sectional drawings. After the walls
have been plastered as hereinafter specified, and the mortar is dry,
pack the earth in against the walls, and after the roof is on cover the
same with earth, as shown by the drawings, and slope it from the top of
cave as indicated.

STONE-WORK.

The walls of the cave to be of stone, eighteen inches thick; these to
be built with good, flat, building stone, the walls to be laid by and full
to a line both faces, and the walls to be properly flushed and pointed;
the walls must be filled solid, leaving no empty spaces in them.

The stone walls are to start four inches below the finished line of
floor of cave, lay the footings of same on a bed of cement mortar not
less than one inch thick, the same extending well outside of the walls.

All of the stone work to be laid in mortar made of clean, coarse,
sharp sand and a good quality of cement, mixed in the proportion of
three of sand to one of cement ; all to be mixed dry, and only wetted
up as fast as used.

The outer face of the walls to be plastered with a good coat of ce-
ment mortar, the same to be carried down to the mortar under the
wall, the mortar made in same manner as specified above for the stone-
work.

If brick is used for the walls instead of stone, substitute the follow-
ing for the above : —

BRICK WALLS.

All brick used in the construction of the cave must be *' thoroughly
hard-burned brick," no soft brick to be used in any part.

Start the brick walls on a bed of cement mortar at least one inch
thick, and four inches below the finished floor of cave ; this mortar to be
made of clean, coarse, sharp sand and a good quality of cement, in
parts of three of sand to one of cement.

Construct the brick walls in the best manner, all to be eight inches
thick, built of hard -burned brick laid in cement mortar; the walls to be
properly bonded with headers every sixth course, every course to be
flushed solid, leaving no empty spaces in the walls — the inside of the
walls to have the jomts neatly struck, and the outer faces of the walls

must all be plastered with a go©d coat of cement mortar, the same to
be carried down to bottom of the walls. All brick must be well wet
before laying.

IRON-WORK.

Provide iron-work for the support of the roof, as shown by the draw-
ing of same.

Support the roof of cave with two six-inch I beams weighing 40 lbs.
per yard, to form skewbacks for the arches ; place 3x5 angle-irons on
the walls, and connect the whole with three lines of iron bolts one inch
in diameter, the bolts to have nuts, etc.

Support the roof of the passage as shown, using 3x5 angle -irons on
walls to form skewbacks for the arches, place one-inch iron bolts as in-
dicated, the angle-iron to weigh 30 lbs. per yard.

ARCHES.

Construct the arches forming the roof of the cave as shown by the
sectional drawings, using only hard, well-burned brick, no soft brick to
be used; the arches to be two '* row-locks," as indicated, and to be
built on proper centering. The brick must all be soaked in water be-
fore using, to be laid with cement mortar, and the joints to be made
close, and filled solid, leaving no empty spaces in them. All joints to
be well slushed up with cement mortar.

Fill in on top of the roof of cave and passage, as shown on the sec-
tional drawings, with concrete made of clean, coarse, sharp sand,
broken stone-chips, or coarse gravel, and a good quality of cement; the
top of the cave and passage to be of convex form as indicated, so that
it will shed water. Top to be made flush and smooth.

PITCH.

The whole top of cave and passage to be covered with a good heavy
coat of good roofing pitch, this to be applied hot and the roof to be
made water-tight thereby.

FLAG-STONE OVER EXIT.

Provide and place over the exit-passage, as indicated on the draw-
ings, a flag-stone not less than five inches thick ; set same in cement
mortar, and pitch the joints to make water-tight.

Provide a stone sill to the outer exit-opening ; this to be four inches
thick.

FLOOR OF CAVE.

Spread a bed of cement mortar two inches thick on the ground in
the cave and the passages; this to be leveled off true and smooth, and
covered with one course of hard-burned brick laid flat, the joints of
which are to be thoroughly grouted in cement.

VENTILATION.

For ventilation of the cave provide two lines of twelve-inch, salt-
glazed, vitrified tile; provide 1-4 bends as shown, and carry tile up to
six inches above the finished grade, as shown by drawings; the
joints must all be made tight with cement, and the outer openings of the
tile to have iron gratings as shown.

DOORS.

Construct two doors as indicated on the plans, these doors to be of
two-inch planed and matched pine stuff; the same to be battened on the
back, the same put on with screws, and to be hung to the frames with
large, heavy T hinges.

The door-frames to have sills of oak, the jambs to be of pine two
inches thick, the same rebated for the doors; the jamb to which the
door is hung to be four inches wider than the others; this to project
into the cave, so as to secure the hinges to it. Provide the doors with
heavy thumb-latches, iron bolts, staples, and a padlock to each door.

The head-jamb of the door-frames and the sills of same to project
three inches into the walls at sides.

Provide lintels of segment form, as indicated on the drawings, over
door-openings on which arches of brick are to be turned as shown.

SEAT AND STEPS.

Construct seat and steps as shown on the plans; all of sound dry
pine, two inches thick, to be planed and constructed and put up in a
good, substantial manner.

OPENING IN CELLAR WALL.

Cut opening through the cellar wall of the dwelling as indicated, for
the passage to cave, properly fill out the jambs of the opening and fin-
ish plumb and true.

FOR A HOUSE WITHOUT A CELLAR, INCLUDE THE FOLLOWING :—

The wall of the passage to be carried under the house as shown on
the plan.

Cut out the floor-timbers, floor, etc., in the house, and frame trim-
mers, headers, etc., as required for the proper support of the floor.

Construct trap-door as indicated, with flooring same as in the room,
the door to be battened on the back, the battens to be put on with
wrought nails, the door to be hung with heavy 8-inch T hmges and
trimmed with ring and staple to open.

Construct a flight of stairs leading to passage, as indicated on the
plan ; the stringers to be of two-inch pine plank and the treads of 1 i -4

inch pine stuff, the edges chamfered 3-8 inches, the treads to be housed
into the stringers, and the whole well nailed and put together in a sub-
stantial manner.

For the construction of the walls of wood in the place of brick or
stone.

Construct all the walls of cave and passages with 2x4 inch pine
stuff, laid the flat way, all well spiked together, the joints to be prop-
erly broken at the angles and corners; the stuff to be placed horizon-
tally and to make walls four inches thick without exterior covering.
This stuff should all have a good coat of coal-tar, applied hot, and same
to cover all four sides of the stuff'; this to preserve the wood.

Cover the outside of the above walls with 7-8 planed and matched
pine stuff, this also to be coated on both sides with coal-tar; these
boards to be placed vertically, and all well nailed.

Construct the roof with 2x8 stuff, placed on edge and close together,
forming a solid roof eight inches thick in the center; the ends of same to
be cut down to six inches, so as to form a pitch for the roof, which will
slope from the center to either side. Cover the top of roof with 7-8
matched pine stuff, all well nailed; the above roofing to be covered with
coal-tar, same as specified for the side walls. Cover the roof-boards
with a good coat of roofing pitch. Construct the roof of the passages
in the same manner, using 2x6 stuff and cutting down to 4 at ends.
The floor, arrangement for ventilation, doors, etc., to be the same as
specified for cave built with stone or brick.

Of cost of tornado-cave, in accordance with design for same pre-
sented by John R. Church, architect, Rochester, N. Y.

Note. — Estimates are based upon following prices for materials and
labor : —

SPECIFICATION

WALLS.

ROOF.

ESTIMATES

Excavation

Building stone

Brick

Sand

Cement

Iron

Pine lumber (rough)

Tile

Pitching roof

Labor, mason

Labor, laborer

.30 per cubic yd.

6.00 per cord.

8.00 per thousand.
1.50 per cubic yd.

18.00 per thous. ft.

1.25 perbbL
.03 Vi per lb.

.40 per ft. lin.

.05 per sq. ft.
3.00 per day.
1.50 per day.

Estimate for cave connected with house having cellar. Walls of cave
of stone. Includes labor.

100 cubic yds. excavation $ 30.00

Stone-work, 50 perches (of 16 ^ cubic ft.) 112.50

Concrete and plastering 30.00

Flooring, 600 brick 8.40

Roof, 2,700 brick 37.80

Flag-stone over exit 12.00

Stone sill at exit 2.00

Pitching roof, 300 feet 15.00

Iron- work, 750 lbs 24.38

Tile for vent. .\. 10.00

Laying same 3.00

Gratings for vent opening (2) 2.00

Doors, seats, etc 12.00

S299.08

Where the cave is to be used independent of any building, and
passage to house is omitted, deduct from the above figures the sum
of $62.30, making the estimated cost of cave under those conditions
I236.78.

Estimate of the cost of cave with brick walls connected to house
having cellar. Labor included.

85 cubic yds. excavation $ 25.50

8,100 brick in walls 113.40

600 brick for floor 8.40

2,700 brick for roof 37.80

Flag-stone over exit 12.00

Stone sill at exit 2.00

Pitching roof, 300 feet : 15.00

Iron- work, 750 lbs 24.38

Concrete and plastering 30.00

Tile for vent 10.00

Laying tile and trenching 3.00

Gratings for vent 2.00

Doors, seats, etc 12.00

$295.48

Where the cave is to be used independent from any building, and
the passage to cellar is omitted, deduct from the above figures the sum
of $60.88, making the estimated cost of cave under those conditions
$234.60.

Estimate of cost of cave v/ith brick walls, connected with house
having no cellar. Labor included.

110 cubic yds. excava^tion $ 33.00

10,200 brick in walls 142.20

600 brick for floor 8.40

2,700 brick for roofing 37.80

Concrete, plastering, etc 32.00

Flag-stone over exit 12.00

Stone sill at exit 2.00

Pitching top of roof, 300 feet 15.00

750 lbs. iron in roof - 24.38

Tile for vent, 23 feet, 3 bends 10.00

Laying tile and trenching 3.00

Gratings for top of tile 2.00. .

Doors, seats, etc.. 12.00"^

Stairs, trap-door in house, etc , 10.00

1344.38

Estimate of cost of cave having stone walls,, connected with house

having no cellar. Includes labor.

126 cubic yds. excavation $ 37.80

Stone-work, 62 perches (of 16^ cubic feet). 139.50

600 brick in floor 8.40

2,700 brick in roof 37.80

Concrete and plastering 32.00

Flag-stone over exit 12.00

Stone sill at exit 2.00

Pitching roof 15.00

Iron-work, 750 lbs 24.38

Tile for vent 10.00

Laying and trenching same 3.00

Gratings for vent 2.00

Doors, seats, etc 12.00

Stairs, trap-door, etc 10.00

$345.38

Section of Cave. Woodconstruction.

Estimate of cost of cave, walls constructed of wood, and connected

with house having cellar.

Excavation, 85 cubic yds $25.50

3,000 feet rough pine 54.00

1,000 feet matched stuff 20.00

Labor on above 35.00

Tarring roof and lumber 20.00

Floor, brick and cement 12.00

Tile for vent, laying same and giating 15.00

Doors, seat, etc 12.00

$193.50

Where the cave is to be used independent from any building, and the
passage to house is omitted, deduct from above figures $39.00, making
tine estimated cost under those conditions $154.50.

For walls constructed of wood as above, connected with house
having no cellar, add to above figures the sum of $25.50.

Remarks upon the Construction and Use of Tornado-caves,
BY Lieut. Finley.

The importance of securing absolute protection against bodily injury
from the violence of tornadoes cannot be questioned, and there are few
people who now speak lightly of the necessity of resorting to extraor-
dinary means in the presence of the king of storms. The word extra-
ordinary " is used advisedly, because ordinarily man obtains immunity
against the fury of the elements by refuge in the usual forms of habita-
tion; but the dreadful force of the tornado compels us to ignore all
places of security ^here the structure rises above the surface of the
ground.

Let us take an example, illustrating the force of the wind. Assume
the progressive velocity of the storm to be twenty-five miles per
hour. Suppose a house 24 x 30 feet on its foundation exposes a plane
surface to the wind of 720 square feet. Twenty-five miles per hour is
equivalent to about two pounds pressure upon each square foot of sur-
face, presented at right angles or perpendicular to the direction of the
wind. On 720 square feet of surface the pressure exerted at right angles
to it would be 1,440 pounds. This is not enough force to move the
building, because it is much less than the actual weight of the structure,
and therefore insufficient to overcome its point of stability. But twenty-
five miles per hour is simply a brisk wind.

Air moving with a velocity of 100 miles per hour against the building
here referred to would exert a pressure of 21,600 pounds upon its ex-
posed surface of 720 square feet. With a velocity of 500 miles per hour
the pressure would be increased to 486.000 pounds, or 243 tons. This
enormous pressure is but about one-half of that which would result in
the case of a perfect vacuum in the tornado's vortex. In a perfect
vacuum, the air rushing into it would move at the rate of about 1,400
feet per second, which would be nearly equivalent to a velocity of 1,000
miles per hour. The pressure upon each square foot of surface exposed
to such a velocity would be about 2,700 pounds per square foot, or if
thrown upon the entire building, that is, 720 square feet of surface, i,-
944,000 pounds, or 972 tons.

The force here assumed is force acting only in right lines. But when
it is understood that in the actual tornado the forces in play are ex-
erted both in right lines and in curved lines, the destructive power is
seen to be of almost incalculable fury and energy. In the majority of
instances the determinations as to the force of* the wind in a tornado
have ranged between 100 and 500 miles per hour. Theoretical veloci-
ties of over 2,000 miles per hour, based upon certain assumed atmos-

pheric conditions, have been deduced. Such velocities are mathemati-
cally possible, but not meteorologically 'probable. What has now-
transpired shows the absolute and undeniable necessity for an under-
ground retreat to secure protection from the tornado.

Hints.

1st. Locate the cave west of the house, so that if the building is de-
stroyed the debris will not be as likely to be thrown upon it, the storm
always coming from the southwest quadrant.

2d. The entrance and exit to the cave should be east of the cave
proper and connected with it by a tunnel or chamber, and securely pro-
tected from mjury.

3d. It is preferable that the entrances should connect with the cellar
of the house, or if there is no cellar, then by means of a trap-door
within the house leading by a stairway to the underground chamber,
which finally connects with the cave proper.

4th. The entrance way should have two doors, one at the beginning
of the chamber or tunnel, and the other at the end opening into the
cave, as precaution agamst the intrusion of fire and smoke, where the
debris of the house might be destroyed by fire.

5th. The entrance and exit should be independent of each other, and
the latter lead out to the open air by a short chamber with two doors,
one exterior and the other interior, the latter opening into the cave
proper.

6th. The roof of the cave should always be arched, because offering
more resistance to the force of the wind and falling debris than a plane
surface. The upper surface of the roof should be at least three (3) feet
below the earth resting upon it. This precaution gives additional pro-
tection against driving timbers thrown by the force of the wind.

7th. The excavation for masonry work should be of sufficient depth
to permit the upper surface of the roof of the cave to rest about one foot
below the surface of the (surrounding) undisturbed earth. This arrange-
ment, hy allowing three feet of earth to cover the roof, will raise a
mound of about two feet, which, while serving as a protection to the
masonry, will also serve to turn the surface-water away from the roof
of the cave.

8th. The earth covering the roof should be well pounded. It may
be mixed with broken stone. The surface should be sodded or sown
with blue grass. Every precaution must be takeu to render the earth
above the roof of cave proof against flying missiles and timbers, which
are frequently driven several feet into the solid earth.

Qth. Stone or brick, with Akron or Portland building cement, is the
best material for purposes or construction.

loth. It is folly and false economy to build a cave without taking
every precaution to prevent decay of materials used.

nth. Drainage. Particular attention should be paid to constructing
the cave in such a manner that it v^^ill keep dry. If possible, a dry
cave should be constructed by laymg all masonry in cement mortar
and carefully pointing the exterior of all w^alls, and then plastering on
the outer faces with cement mortar.

The roof should take the convex form suggested, and should be cov-
ered with a good coat of coal-tar or roofing pitch.

The cave should never be connected with the house-drain, cess-
pool, or sewer, receiving waste from the house, on account of the diffi-
culty of so disconnecting same as to prevent the entrance of sewer-gas
into cave — as during the dry season the water-seal of the trap would be
likely to be broken from evaporation and other causes.

The cave should not be connected with a cesspool receiving waste
from the house, on account of the possibility of same overflowing into the
cave.

1 2th. Where practicable, the entrance and exit doors which open into
the cave proper should be of iron, or oak covered with sheet iron.

13th. Careful attention should be given to secure complete and un-
disturbed ventilation of the entire cave.

14th. During the season when tornadoes are most likely to occur, the
cave should be provided with all things necessary to place it in readi-
ness for occupation at any moment of night or day. Every precaution
should be taken to keep the entrance and exit ways free from all obsta-
cles that might prevent or delay the immediate use of the cave. The
cave should always be provided with the means of lighting it, say,
safety-lamps or lanterns.

15 th. Every one constructing a tornado-cave should bear in mind the
necessity which may occur of their being compelled to use it as a home
for a considerable time while repairing or building anew from the ruins
of the storm. Therefore, where it is possible, it is of the utmost im-
portance to erect the tornado-cave with care, thoroughness, and a due
regard to comfort. The poor man, if he must build slowly for
lack of funds, should build exceedingly well, while the rich can con-
struct rapidly, thoroughly, and with every regard for comfort and adorn-
ment. But in either case the absolute protection from injury and loss
should be the same, because the poor man cannot afford to waste money
and time, and subject himself and family to great danger, by reason of a
hasty and improperly constructed cave.

1 6th. During that season of the year when tornadoes are not likely to
occur, the tornado-cave may be turned to practical account for the
storage and safe keeping of many thmgs necessary for household use.

17th. The cave proper may be constructed in circular form, with con-
vex roof, as perhaps being more durable and economical of space than
the angular form with convex roof, but whatever the particular fancy of
the builder may dictate, let the work be done thoroughly and with the
best materials.

With regard to the protection of life and property in the many small
towns, and even cities, liable to be visited by the devastating tornado-
cloud, what has already been suggested in the manner of north and
south movements, dug-outs, and cellar-caves will, of course, apply here.
Where, as in a village or city, a large number of persons are congregated,
each intent upon his or her particular business, it is hardly to be ex-
pected that they will have the leisure to observe, or be inclined to give
any attention to the face of the sky. Should it chance that any per-
son watched the atmospheric changes and received indications of the
approach of a tornado-cloud, he might not think it his duty (probably
forget it in his excitement) to warn others of the impending danger, or
provide for the safety of more than his own family. Of course, in any
event it is natural to suppose that he would first secure his own household.
This supposed case is a very probable one; at least nine times out of ten
we find that towns are devastated without apparent warning, and the un-
fortunate people, startled from their imagined security, are killed in
their struggling efforts for escape. Some provision should be made for
the mass of inhabitants who are performing their various duties in and
out of doors, and who by reason of their peculiar situation or labor
could not, if they would, ascertain the prognostics of the sky.

With regard to this matter we will offer a few suggestions which may
not be amiss. On any day when there is presaged in the weather condi-
tions evidence of the probable approach of a violent wind -storm, it
should be the duty of those in authority to deputize certain intelligent
persons to watch the character and approach of the storm and, if a tor-
nado, to give timely warning of its advance to the various families in
their respective wards, and take charge of the removal of persons and
property to places of safety. The church and school bells might be
rung in a peculiar manner as a signal of warning. These men should
be cool, brave, active, and judicious. They should understand the situ-
ation, know precisely what is needed and how to supply it. All per-
sons should at the proper time appreciate the situation of those in
authority and avoid confusion by a strict compliance with orders.

The signs (as before described) ot tornado-cloud formation and ap-
proach are distinct and sufficiently suggestive to afford opportunity for
timely and concerted action. The time for action will necessarily be
limited, and the watch need not commence until there is every reason to
believe that such a course is absolutely necessary. Some persons may
be disposed to smile at the novelty and minuteness of this arrangement,
or at the idea of employing weather-guards at Western towns. I will
venture to say that these smiles will not appear on the faces of persons
who have experienced the irresistible and overwhelming violence of a
tornado. I have never detected levity or indifference among those who
were left to tell the tale of distress in any of the many almost annihilated
towns of the West. You may smile or wonder at the thought of hardy,
brave men who have, without flinching and in support of their country's
honor, faced the red-hot belchings of a score of batteries, who now at
the sight of a threatening cloud or the experience of a brisk wind, make
a bold dash for places of safety, or, throwing themselves upon the
ground, clutch at the first object within reach. Such is the abject terror
which possesses all alike after the experience of a tornado.

Immediately following and for some weeks after the occurrence in
Kansas and Missouri of the violent tornadoes of 1879, hundreds of people
along the tracks and in the vicinity of the storms hardly went to bed,
but remained dressed and, with their lanterns trimmed and burning,
watched intently every foreboding appearance of the sky. Every dark
cloud or sudden increase of the wind was calculated to affect them with
an indescribable terror which could not be allayed until every vestige of
the supposed danger had vanished. This is not the pitiful tale alone of
Kansas and Missouri sufferers, but wherever the dreaded tornado makes
it way, be it in Michigan, in Mississippi, in Georgia, in Massachusetts, or
in Minnesota, the awful roar and power of its march strike all life dumb
with fear. A great deal can be accomplished towards allaying this fear
by a dissemination of practical knowledge concerning storms and by a
general effort among intelligent people to appreciate such information.
All intelligent persons can and should become familiar with the various
classes of storms and be qualified to detect their formation and approach.

There is no country on the face of the globe where meteorology can
be studied with so much advantage, practically and scientifically, as in
North America. The elementary principles of meteorology, especially
in regard to storms, should be taught in every school, country, town,
and city. In the colleges and universities an advanced course should
be prescribed. Speculation regarding the weather is exceedingly rife,
affecting every branch of the science and in a manner quite without
precedent in the line of methodical knowledge.

Tornado prediction is no longer a mere possibility, but in many re-
spects may be considered an accomplished fact. By this I do not mean
absolute perfection, but reasonable success. The system of preparation
and study which leads to the result is subject to improvement, both as
to manipulation of charted data and the verification of forecasts; but it
is believed that the work now in hand with the above end in view, will
greatly enhance the present measure of success. Tornado predictions
have been made daily, largely as a matter of study, but in part for the
information of the public, through Signal Service official bulletins, since
March 1st, 1884.

That all people may know and become impressed with the excep-
tional power and awful grandeur of the tornado, illustrations of its work
in particular instances will be opportune at this time.

REPORT ON THE TORNADOES OF MAY 29TH AND 3OTH, 1 879, AT
SALINE COUNTY, KANSAS. PROFESSIONAL PAPER OF
THE SIGNAL SERVICE NO. IV., BY LIEUT. FINLEY.

On the 30th of May, 1879, about 3 p. m., a tornado
passed over a portion of Saline County, Kansas, concerning
which the following graphic description was prepared by an
eye-witness : —

''It rains so gently this afternoon that the weather is really
enjoyable. Plants grow and flowers bloom as they never do
when it is dry. The Solomon Valley seems almost a second
Garden of Eden. A short time before the clock strikes
three, hailstones begin to fall, which rapidly increase in
size. We gather some of the largest and find that it takes six
of them to weigh a pound. But notice that hail-cloud south
of us ! What wonderful contortions, evolutions, and twistings.

Note. — Pictures of the identical storms described are not obtainable,
and, per contra, descriptions of the storms photographed are not at
hand; but as one tornado is essentially the counterpart of another, we
have adopted such pictures as we could get to illustrate the destructive
force of these terrible meteors. There is no pretense that the pictures
represent the events narrated other than in their characteristics. With
this explanation no one need be misled by the juxtaposition of text and
plate, which are in reality foreign to each other.

The hail that is falling from it is plainly visible from here,
although it is four miles to the southwest. A few strips
of cloud like whip-lashes hang from it.

Tornado at Griiuiell, Iowa, June 17, 1882. View near tho residence of Mr.
Graham, looking northeast. From a Photograph.

''The cloud now revolves rapidly from right to left. We
gaze at the magnificent scene with awe and wonder. The
center becomes lower and lower, until it resembles a funnel

Tornado at GrinneU, Towa, June 17, 1882. Debris of Dr. Ford's dwelling, ^

looking east. From a Photograph. \

The truth now bursts upon us. // is a tornado! We hear its |

awful roar like an earthquake or distant thunder. The fun- i

nel rapidly descends till it reaches the earth. It moves rap-
idly northward. It rises, a dark cone ascends from the
ground to meet it, and it descends. It strikes the river. All
the water is drawn from the channel, perceptibly widening
the cone. From the first the tornado has had the appearance
of a waterspout at sea. We think it is coming near us. We
can now see its fury. It is not far away. Shall we leave the
house ? No, for we are not certain on which side it will
pass. We are apparently as safe here as elsewhere. We can
only trust in Providence. The windows are nailed fast.
Three of us lean against the door which is nearest the storm.
The rest go into the cellar. It is about 4 p. m. A moment
of breathless suspense and the storm strikes us. The timbers
creak, the sides of the house sway in and out. Surely, they
cannot outlast it. We hear no well-defined roar now, for on
the outside, boards and other debris are fiercely clashing. All
is dark within. In about fifteen minutes the storm is over.
We leave the house. The center of the storm has passed to
the west of us and we can see its dark form moving away in
a northeast direction. "

After leaving this point a neighbor was visited, and with
what awful results! It makes the blood chill in the veins to
rehearse the horrors of the scene. Wild and dreadful was the
carnage of that hour. The buildings, the hard earnings of
many years, were swept from the earth. A large, two-horse
sulky plow, weighing 700 pounds, was carried a distance of
thirty-five rods, breaking off one of the iron wheels attached
to an iron axle if inches in diameter. Two stoves were
found broken into small pieces, not any of them larger than
six or eight inches square. Wagon hubs without a single
spoke in them, wagon tires curled into fantastic shapes,
pieces of clothing and bedding wound about sticks and tim-
bers or scattered over the prairie, were the only signs of a
once thrifty home. Upon the destruction of the house one
of the daughters was ca^rried by the wind 200 yards to the

northwest, and thrust head foremost into a barbed-wire fence.
She was almost instantly killed, the clothing was stripped
from her body, which was found covered with black mud
and her hair matted with it. The posts along the fence for a

Tornado at Grinnell, la., June 17, 1882. General view looking in direction
taken by the storm. From a Photograph. Dr. Grinnell's house in background.
Shadow under the floor shows the place from which he took his wife and four
children unharmed.

distance of twenty-five rods were covered on the south, side
with mud, straw, chaff, and bits of rags to a depth of nearly
three inches, and near the bottom of the posts it was one

foot thick. It was plastered on as if thrown with the greatest
velocity, requiring a sharp instrument and considerable phys-
ical exertion to make an impression upon it. Five of the
posts were literally pulled out of the ground from a depth of
twenty-eight inches. The wire was stripped from the posts
and wound up into a ball. The eldest son was carried thirty
rods to the northeast into a wheat field, his clothing torn into
shreds, and his body covered with black mud. Another
daughter had a piece of board driven nearly through the
fleshy portion of her thigh, cutting a gash about seven inches
wide; the board was pulled out of the flesh during the storm,
probably by the violence of the wind. The ghastly wound,
upon being examined by the attending surgeon, was found to
contain pieces of nails, straw, mud, and splinters of wood.
In all cases women suffered the most, as they were divested
of their garments and left perfectly at the mercy of the flying
debris that filled the air. The hair of all persons caught in
the midst of the storm was so matted with mud that their
heads had to be shaved in order to clean them. It seemed as
if the mud belonged there naturally, and that the hair was
but a mere usurper. Eyea and ears were also filled with
mud, preventing the natural use of these senses. All of the
wounds received were torn and 'jagged, and found mostly
upon the back of the body and running upward. Two
strangers passing by at the time of the storm stopped at the
barns to seek shelter. One of them was repeatedly dashed to
the ground and rolled about until death came to release him
from his sufferings. The other took refuge in a straw-stack
which was turned over upon him, and then finally scattered
in every direction. When completely left to the mercy of the
elements he was lifted in the air, how high he did not
know, but while above the ground he came in contact with
the tail or mane of a horse, which he grasped, but was finally
separated from, coming down to the earth, with hat in one
hand and hair in the other. A light, two-horse wagon, with

one horse attached, the other being killed by flying debris,
was observed at a height of about loo feet in the air. A
large barn forty feet square, with sixteen-foot posts, v/as com-
pletely demolished, and every timber carried away from the

Tornado at Grinnell, Iowa, June 17, 1882. General view looking east.
Wrecked buggy with spokes blown out of hub. From a Photograph.

foundation. Six horses were killed, two outright, and the
others so seriously injured by flying debris driven into their
bodies that they had to be shot. One animal was badly
mangled about the body, and bad nearly all of its bones

broken, having fallen from a considerable height, making a
large depression in the tough sod of the prairie. Eighteen
fat hogs, weighing from 300 to 500 pounds each, were killed
outright, and six others died afterwards from their injuries.

Tornado at Grinnell, Iowa, Juno 17, 1882. Ruins of Geor^re Parse's resi-
dence. From a Photograph. Six wounded. Mrs. Parse blown 50U feet.

One hog weighing 300 pounds had a scantling seven feet
long and six -inches square driven lengthwise through its
body. Another had a fence-board driven through it in the
same manner, and still another had a sharp-pointed post

driven through the body from side to side ; one was carried
300 yards out on the prairie. Two new lumber wagons
were carried from thirty-five to fifty rods in different direc-
tions and torn to pieces. One of the wheels was carried a
distance of one mile to the northwest. In other instances
wheels were broken from the axles, the spokes twisted from
their sockets, and the large, heavy, iron tires twisted into the
most fantastic shapes. A log twelve feet long and ten inches

Tornado at Grinnell, Iowa, June 17, 1882. Ruins of Dr. Grinnell's resi-
dence. From a Photograpli.

in diameter was carried 320 rods to the northwest. The
front iron axle ( inches in diameter) of a top buggy was
found bent double, the two ends crossing each other, and
both wheels were torn off even to the hubs. The rear axle,
with wheels attached, was carried one quarter of a mile to the
northwest. A wooden sill eight by ten inches and sixteen
feet long was carried twelve rods to the northwest. A cat
was found half a mile northeast of the house in which she

was seen just before the storm, with every hone broken and
the body crushed as flat as if it had been passed through a
cider-press. Chickens were stripped of their feathers and
carried long distances, one being found three miles to the
northeast.

The iron mold-board of a heavy, wooden-beam plow was
found driven into the ground so firmly that it had to be dug
out. Osage hedges were filled with debris that defied re-
moval without digging the bushes from the earth.

THE lee's summit TORNADO, JACKSON COUNTY, MISSOURI.
MAY 3OTH, 1879.

''At a little past 7:00 p. m. I saw the funnel-shaped cloud
whirling terribly and approaching from Mr. Hutchins. I
was standing near the center of the south frame part of
the house, and rushed to the south door to hold it, but
before I could pull a chest to the door from a distance of
ten feet the storm-cloud was upon us. The wind struck
the south end of the house first, raising it from the foun-
dation ; then the log and frame parts to the north were struck
upon the east side, also raising them from the foundation,
when the top of the entire house fell in, and the whole
confused mass was turned over twice to the northwest. It
was left there but for a moment, apparently to give the
whirling current time to pass around the barn to the west
and south, which it did without injuring it, but throwing
down the surrounding trees."

Returning to the house, \yhich it did almost instantly,
the violent southwest current carried all but the west
side back to the north, a distance of several hundred
yards, smashing everything into kindling-wood. No
part of the roof and upper floors could ever be found.
Mr. Warden, Jr., was carried with the house to the north-
west, and while the current passed to the barn, was held
between two of the floors and badly bruised, and on the

return of the current was carried to the north 200 yards.
His father and younger brother pursued about the same
course, except that the former was blown to the northwest

Tornado at Kansas City, July 17, 1880. Ruins of Carrigan's barn, cor. 17th
St. and Madison Ave. From a Photograph.

and there remained with the west side of the house, while
the latter was carried to a point within a few feet of his
elder brother.

All of the parties were covered with mud from head to
foot ; eyes, mouths, and ears filled, and clothing torn into
shreds. The elder son had his head and face cut, and
shoes torn from his feet, one of them being found at the
house, and the other carried one-fourth of a mile to the
northeast. His trousers and shirt were torn into strips,
hair matted with black mud, his face bruised, and dirt
driven into the flesh.

The mother and two small children were left in the
rubbish, the former having her head crushed, and her long
hair, which reached below her waist, was partly cut and
partly torn from the scalp, twisted into a rope, and found
several feet from her body. That portion of the hair left
upon the scalp was twisted into little wisps and mixed
with mud. The baby was thrown to the southeast about
twenty yards, and another child was carried to the west
112 feet, and two large splinters driven through its thigh,
one of which came from Mr. Hutchin's house, one-fourth
of a mile to the southwest, it being identified by the pecu-
liar color of the paint upon it. A little girl was thrown
six rods to the northwest and uninjured. In all cases cuts
were made only upon the heads, and bruises upon the body.
All the members of the family had their hair matted with
mud and their clothing so filled with it, that it was impossi-
ble, even after a number of washings, to render the gar-
ments fit for use.

The bodies of most of the children, after having been
washed daily for four days, were still covered with specks
of fine dirt and bits of leaves, which seemed to be driven
into the flesh.

The following will indicate some of the peculiar freaks
of the storm : A carpet upon the floor of the log part of
the house and securely tacked about the edges was taken
up and carried out of the house without being torn. A
new sewing machine was broken into forty or fifty pieces.

Fine feather beds were torn into strips, and the contents
scattered broadcast over the country. Several garments
were carried five or six miles to the northeast. An iron
kettle holding fifteen gallons was broken into six pieces,

Tornado at Kansas City, JtQy 17, 1880. Mr. Doggett's house, cor. IGtli and
Dripps Sts. From a Photograph.

and scattered about in several directions. A ten-gallon keg
filled with vinegar was carried to the northeast forty rods.
A large iron-bound trunk, fitted with an extra heavy lock,
was torn to pieces and the lock found a half mile to the

northeast, sticking into one of the rails of a fence. Several
photographs, which were known to have been securely placed
in an album* which was packed in the trunk, were found on
the ground, a distance of over four miles to the northeast.
A vest belonging to i\Ir. Warden and containing his watch,
was carried out of the house. The watch, becoming sepa-
rated from the vest, was carried by the wind fifty yards to

Tornado at Kansas City, Jtdy 17, 1880. Mr. Post's house, 19th and Mercer
Sts. From a Photograph.

the northeast, and found covered with mud. The vest was
carried to the east a distance of twenty yards. Several
chickens were carried to the northeast, a distance of about
one mile, and entirely stripped of their feathers. Two
stoves were broken into small pieces, but one standing
near the middle of the house escaped uninjured.

Heavy bed-quilts were so filled with mud that when
dry they were as stiff and hard as boards. A lumber
wagon was carried to the northwest ten rods, the box torn
to pieces, and nearly all of the spokes taken out of the
wheels. An iron-beam plow, standing twenty-five feet
west of the house, was not moved or injured, and a seed-
drill and harrow, near the barn, were also untouched. The
debris from the house was scattered over a region of coun-
try one mile wide by five miles long. The path of great-
est destruction was eighty rods wide, but fences were torn
down for a breadth of nearly two miles.

Another dreadful disaster in the course of this storm
occurred at the house of the ill-fated Harris family. It was
situated in a little ravine near one of the branches of Sni-a-bar
Creek, one-half mile east of Blue Springs, and sixty feet west
of the storm's center. The family, consisting of father, mother,
and four children, ran out of the house on the approach of
the storm, the former and one or two of the children first
moving to the northwest, but thinking that the cloud was
coming directly towards them in that position, they turned
back to the east, and by the time they had reached a point
about on a line with the storm s course, they were struck by it.

The father and baby were carried into a field northeast of
the house, a distance of 150 yards, coveied with mud and
bruises, and found in the agonies of death.

The mother, who had not succeeded in getting as far away
from the house as the two former, was carried to the east
seventy-five yards, and lodged against a small tree, around
which her body was partially twisted. Her skull was
crushed, and she died in a few minutes after being found.
Her clothes were stripped from her body, which was bedaubed
with mud from head to foot. One girl, eight years old, was
found dead and mangled in the center of the storm's path, a
distance of fifty yards northeast of the house. One boy was
blown into a straw-stack, a distance of forty-five yards to the

northeast. A little girl was found eighty yards to the north-
east, lying in the center of the storm's path. The two latter
were not dangerously injured.

Those who examined the bodies of the dead, among them
a physician, stated that after they were washed the entire sur-
face was found to be ecchymosed ; or, in other words, they
had been so severely bruised and dashed about by the vio-
lence of the wind, that the flesh was nearly black by the
settling of the blood in the tissues of the skin.

The ground upon which the house stood was swept as
clean as if scourged by fire. There was hardly a vestige
of clothing anywhere to be found. Now and then a small
rag could be seen fluttering from some tree-top, caught upon
a rail fence, or wound around some broken piece of timber.

The creek, about half a mile southeast of where the house
stood, was found choked up with a mixture of straw, rags,
feathers, kitchen utensils, rails, boards, household furniture,
and pieces of farming implements. Wagon hubs were to be
found with every spoke gone, some broken ofl" and some
pulled out. Two heavy quarter-inch wagon tires were
twisted into knots. The iron mold-board of a plow, one-half
inch in thickness, was broken in two, and one of the
parts driven into the ground a depth of 9^ inches. There
was not a single farming implement or article of furniture
that was not rendered unserviceable.

TORNADO AT MARSHALL COUNTY, KANSAS, MAY 3OTH, 1 8 79.

The following relates chiefly to some of the dreadful experi-
ences in the great tornado of May 30th, 1879, at Irving,
Marshall County, Kansas.

'*The funnel-cloud now swept on a mile and a half over
the valley beyond the town, scattering fences and twisting off
small trees until it reached the Big Blue River at a point
about 800 feet south of the large iron bridge. In crossing
the river the clouds struck the heavily wooded bluffs on the
eastern bank, rising from 75 to 150 feet, and turned imme-

diately up the river, striking the bridge squarely from the
south, which it lifted bodily from the two stone piers and one
abutment, and dashed it into the river. So completely

Tornado near Connersville, Ind., May 14, 1883, about 7:00 P. M. Ruins of an
iron bridge lifted from abutments and dashed into the river below. From a
Photograph.

twisted into shapeless ruin was the large mass of iron rods
and stringers that it entirely disappeared from view in a few

feet of water. The superstructure rested upon a heavy stone
abutment at the east end, and upon two stone piers rising 22
feet above the water, one in the center and the other at the
western extremity of the first iron span. From this pier to
the western bank of the river, 140 feet, a wooden trestle-

Tornado near Connersville, Ind., May 14, 1883. See also page 87, anotlier
view of same bridge. From a Photograph.

work completed the structure. Thirty feet of the eastern
end of this trestle was carried away with the iron spans and
deposited in the river. Where the wooden portion separated,
timbers lo to 15 inches square, fastened with heavy iron

bolts, were broken asunder as if they had been pipe-stems.
The iron portion of the bridge consisted of two spans of 125
feet each, and four chords with a rise each of 1 8 feet, weigh-
ing twenty-seven tons to the chord. Several of the large iron

Tornado at Gi iimell, Iowa, June 17, 1882. Portion of train on Iowa Central,
east of track. From a Photograph.

rods, 2 J inches in diameter, sticking out of the water upon the
sandy beach were found broken square in two; smaller ones,
and broad, flat strips of iron were twisted into fantastic shapes.

So easily and yet so completely was the great structure
lifted from its foundation that but two of the top stones were
moved from the eastern pier. This was perhaps the most
terrific manifestation of force ever exhibited by any storm in

Tornado at GrinneU, Iowa, June 17, 1882. Portion of train on Iowa Central
west of track. From a Pliotograpli.

this section of country. The structure was practically new,
having been built but a few years before at a cost of $20,000.
The cloud from this point passed up the river, following the
bends to the north and northwest for a distance of about

i,200 feet, when it reached a small 'draw ' from 250 to 300
feet wide, cutting up through the bluffs to the east and reach-
ing the high prairie beyond. Up this opening the cloud
ascended with terrible fury, uprooting and breaking off large
oaks and hickories 18 inches to three feet in diameter, and
plowing up the earth in deep furrows. While passing up the
river the water was subjected to the extraordinary violence of
the whirling currents of air and forced backward on either
side to the banks, exposing to view the bed of the stream for
a considerable distance. The violent uprush of the air in the
center of the cloud carried the water in spray above the tops
of the highest trees. "

A further description of this storm, in the vicinity of Irving,
Kansas, presents a thrilling account of the terrible devasta-
tion wrought by it. A heavy westerly wirfd, causing consid-
erable damage, prevailed at Waterville and Blue Springs,
eight miles to the northwest. This current passed eastward
to Irving, reaching the town after the first storm had disap-
peared on the high prairie beyond the river. In the wake
of the first tornado a warm southerly wind passed over the
town accompanied by rain. The sun, now partially exposed
beneath the heavy clouds lining the western horizon, threw
its warm rays upon the terror-stricken inhabitants, who, at
this welcome invitation, assuring them as they thought of
peace and^ protection, emerged from their cellars and dug-outs
to witness the destruction already committed and relieve
their suffering neighbors. Hardly had the people recovered
from the first shock, when there appeared in the West a
cloud of inky blackness and enormous dimensions, present-
ing a square front of apparently two miles in width and a
perpendicular height from earth to sky. It moved along
slowly, but with the most inconceivable majesty of force, an
nihilating everything within its reach. The cloud is now
at the outskirts of the town, and as it begins to execute its
frightful mission of death and destruction the earth fairly

quakes and trembles. All nature stands aghast, and every
living thing seeks, but in vain, to find security from the im-
pending danger. Many people actually believe that the
Judgment Day has come, and offer fervent prayers and loud
appeals for preservation. But the hand of mercy stays not
the dreadful carnage. It begins. The awful roar, like the
belchings forth of a thousand Columbiads, drowns the most
piercing cries of the wounded. The cloud strikes into a
cluster of eighteen houses and other buildings filled with
human beings and the accumulations of years.

In an instant everything is swept from the earth in terrible
ruin. Death is experienced in its most dreadful forms.
At the house of a Mr. Keeney, the father, mother, and
grandfather were blown two hundred yards to the northeast,
where they were f6und lying within a few feet of each other
mangled and dead. Mrs. Keeney was dashed head foremost
into the soft ground up to her shoulders, entirely stripped
of her clothing, and covered with black mud. The other
two were partially stripped of their garments and also covered
with mud, which was fairly beaten into their clothes. The
three children of this family were carried by the wind several
hundred yards, stripped of their clothing, their bodies cov-
ered with mud, but they were not killed.

The house of a Mr. Sheldon was crushed to the earth and
portions of the debris carried for miles in the air. A daughter,
twenty-two years of age, was blown to the southeast a distance
of two hundred yards, into a low, wet piece of ground.
Nearly every bone in her body was broken, and the flesh in
many places terribly lacerated by flying debris. The body
was found in a perfectly nude condition and almost unrecog-
nizable, because of the grass and mire beaten into it.
Mr. Leddy's house was surrounded by a grove of cotton-
wood trees and a picket fence. The building was lifted
bodily above the tops of the highest trees and dashed to
pieces upon the earth. The east and south fencing was car-

ried away, and those of the trees left standing were stripped
of every portion of bark and foliage and most of the limbs.
Wound about their trunks and fluttermg from the bare limbs
were fragment of garments, strips of long prairie grass and
scraps of paper. On that portion of the picket fence not
destroyed, there hung shreds of every article of clothing
common to the household; and within a radius of thirty to
forty rods lay portions of chairs, sofas, bedsteads, stoves, tins,
and crockery-ware, mingled with shingles, lath, shedding,
clap-boards, sills, doors, window-frames, etc. The utter des-
olation was dreadful to behold. A few moments before,
health, happiness, and plenty made these homes the scene
of comfort, where now grim death and absolute waste reigned
supreme.

The effect upon those who were left to mourn the tragical
death of friends and relations was pitiful in the extreme.
This prosperous community had been scourged by a fell de-
stroyer more dreadful than either flood or fire, epidemic or
war. It came in the twinkling of an eye and all was gone ;
life, property, happiness crushed and annihilated; swept
with lightning speed into eternity. The little graveyard
was dotted with many fresh mounds. The power of the tor-
nado-cloud for a few moments had sufficed to accomplish what
disease and accident had not done in years. The terrible
storms of May 29th and 30th, 1879, will never be forgotten
in the States of Kansas, Missouri, Iowa, and Nebraska.
Night after night following the storms, hundreds of people
never went to bed ; but, with lanterns trimmed, peered into
the darkness watching for a recurrence of the dreadful scenes
through which they had just passed. Every dark cloud or
sudden freshening of the wind filled them with evil forebod-
ings which could not be allayed until every vestige of sup-
posed danger had vanished. The terror depicted upon the
countenances of the bravest men at the sight of a dark cloud,
though it might be perfectly harmless, was something beyond

description or realization, except by those who could witness
their excitement. Persons were preparing to quit the coun-
try; business of every kind succumbed for a season except
that of generously supplying the wants of the sufferers by
well-organized relief committees. Many acts of self-sacrifice
and devotion redound to the glory and honor of Kansas
people.

THE SOUTH CAROLINA TORNADO OF APRIL i6tH, 1 879.

The following information relates to the tornado of April
1 6th, 1879, near Wakerborough, South Carolina. The data
are taken from the Chief Signal Officer's report for 1879.

VELOCITY AND FORCE OF THE WIND IN THE CLOUD VORTEX.

A pigeon-house exposing 24 square feet of surface to the
action of the wind, and weighing 1,000 pounds, was carried

Tornado at Kansas City, July 17, 1880. Mr. Post's liouse, 19tli and Mercer
Sts. From a Pliotograph.

8o feet and demolished against a house. By adding to this
one-third of its weight for friction , the least possible wind velocity
required to move it is 105 miles per hour. It may have been
twice that velocity. — A one-story house exposing 200 square
feet to the wind and weighing 15,000 pounds was carried a
distance of six feet. Least required velocity, 142 miles per
hour. — A church exposing a surface of 1,000 square feet to
the wind and weighing 50,000 pounds was carried 20 feet from
its foundation and demolished. Velocity required, 116 miles
per hour. — A house exposing 360 square feet of surface and
weighing 25,000 pounds was moved 20 feet from its founda-
tion. Least required velocity, 136 miles per hour. — ^A store-
room weighing 10,000 pounds and exposing 128 square feet
of surface, tilted to an angle of 45°. Velocity required, 144
miles per hour. — A piece of timber weighing 600 pounds, its
greatest surface exposed to the wind being 20 square feet,
was carried 440 yards. Least velocity required, 90 miles per
hour. — A buggy weighing 150 pounds was carried up in the
whirl, and the pieces hung on a tree at the height of 60 feet
from the earth. Distance carried, 300 feet. — Two panels of
fence weighing 150 pounds were carried a distance of 300
feet. — A weather-board was found to have been carried a dis-
tance of six miles, it being recognized by the paint ; weight,
six pounds. — A chicken-coop, strong box, 4 by 4 feet, was
carried a distance of four m.iles; weight, 75 pounds. — A hick-
ory tree 54 inches in circumference at butt, and weighing
3,000 pounds, was lifted out of the ground and moved up a
bank ten feet. — A cart weighing 600 pounds was carried up
in the whirl, torn to pieces, and the tire of one wheel found
1,320 yards distant. — An iron chisel weighing four pounds
was carried 90 feet, and driven into a piece of pine timber a
distance of 2 inches. — Two large hubs of a road-wagon, with-
out spokes, but attached to an iron axle, and weighing 175
pounds, were carried a distance of 750 feet. — A basket of
books weighing 50 pounds was carried a distance of 2^

miles, and found hanging on a tree with the contents intact. —
A cart weighing 400 pounds was carried a distance of 125
feet and demoUshed. — Geraniums in pots were found by the
owner one mile from town uninjured. — A buggy left at a shop
near the center of the town to be repaired, could never be
found. — Letters and books were carried a distance of 6 miles.

Tornado at AuTtJum, Ala., April 15, 1884. EXUBS of a. dwelling. From a
Photograph*

Pieces of matting and dresses *were found lo miles away.
Dead sheep were found shorn of their wool to the bare skin,
by the force of the wind. — Fowls were plucked of their
feathers as if picked by hand. — Birds were killed, and none
were seen in the neighborhood for several days after the
storm.

Tornado at Racine, Wis., May 18, 1883. House twisted from its fonndation.
From a Pliotograph.

On February 19th, 1884, the States of Virginia, North Car-
olina, South Carolina, Georgia, Alabama, Mississippi, Ten-
nessee, and Kentucky were visited with the most terrible de-
vastation by wind ever experienced in this country. From 10
o'clock in the morning until 1 2 midnight sixty tornadoes
occurred in different parts of the above-named States. Rough
estimates placed the loss of property at from $3,000,000 to

$4,ooo,ooo; the loss of life at 800, and the number of
wounded at 2,500. The number of people rendered home-
less and destitute numbered from 10,000 to 15,000, many ot
whom were left in a starving condition. The number of
buildings destroyed was about 10,000. Cattle, horses, hogs,
and other domestic animals were destroyed in great numbers.

Tornado at Springfield, Mo., April 18, 1880. Ruins of Catholic cliurcli.
From a Pliotograph.

The tale of distress, ruin, and death might be readily aug-
mented by reciting the horrors of the Grinnell tornado, which
desolated a large section of central Iowa on the afternoon
and night of June 17th, 1882. The town of Grinnell, with
its fine college buildings, was nearly swept from the earth,
and 130 human souls dashed into eternity in less time than
it takes to relate it.

lOO

The great tornadoes of April i8th, 1880, in southwestern
Missouri, destroying the town of Marshtield, and kilUng over
100 people.

The tornadoes of August 3d, 1885, in Maryland, Dela-
ware, New Jersey, and Pennsylvania, destroying over two
millions worth of property and many lives.

The tornadoes of April 14th, 1886, in Minnesota, destroy-
ing the towns of Saint Cloud and Sauk Rapids, with a loss
of over $500,000 and nearly 100 lives.

Each year sw^ells the record of death and destruction, and
makes the contempladon of these dreadful events, which oc-
cur W'ith so much certainty and regularity, a source of the
deepest concern to those who live in the tornado districts;
and, naturally, turns the mind towards the means for the pres-
ervation of life and indemnification for property loss.

CHART NO. 2.

Chart No. 2 refers to the very remarkable tornadoes of
February 19th, 1884.

On the upper portion of the chart there is delineated the
course of progressive movement of the main storm-center, or
the central area of barometric minimum. By this is meant
the path pursued by the general storm which prevailed over
the northern portion of the United States on the day above
indicated. It is usual to represent the direction of movement
of the center of a great storm by a line. In the cartographical
study of storms by the Signal Service the position of the
center is described at three distinct times during the 24 hours,
viz.: At 7 A. M., 3 p. M., and 10 p. m. To illustrate the direc-
tion of movement and the day and hour of observation,
the following symbol is used, similar to that shown on the
accompanying chart.

18 ' IH 18 19

@ — ^ — © — ^ —

1 2 3 1

The upper figures indicate the day of the month, and the

loi

lower figures show the hour of observation, i is equivalent
to 7 A. M., 2 to 3 p. M., and 3 to 10 p. m. The track of the
general storm is shown for the i8th, 19th, and 20th. On the
lower portion^f Chart No. 2 is shown the position and direc-
tion of movement of the various tornadoes that occurred on
the 19th of February, 1884. The tracks are indicated by the

following symbol : X X X X X X ^ —

The principal object of this chart is to show that a definite
relation exists between the location of the center of the general
storm and the place of tornado action and development. It
is now established beyond question that no tornadic action
ever takes place without the presence (always north and
west of the tornado region) of a general storm or 'Mow/' as
it is technically called, and that, too, of marked intensity
and peculiar form. Now, it is of great practical import-
ance for the public to bear this fact in mind when they are
watching the daiJy bulletins and weather indications of the
Signal Service, which are published broadcast throughout the
country. Whenever a general storm is known to be moving
eastward over the United States in the season of year favorable
for tornadoes, the following deductions, which have resulted
from a long and careful consideration of the subject, should
be thoughtfully studied and clearly understood.

1. There is a definite portion of an area of low pressure
within which the conditions for the development of tornadoes
are most favorable, and this is called the dangerous octant.

2. There is a definite relation between the position of tor-
nado regions and the regions of high contrasts in temperature
(temperature gradient), the former lying to the south and
east.

3. There is a similar definite relation of position of tornado
regions and the region of high contrasts in dew-points, the
former being as before to the south and east.

4. The position of tornado regions, or the area of tornadic
action, is to the south and east of the region of high contrasts

I02

of cool northerly and warm southerly winds — a rule that
seems to follow from the preceding, and is of use when obser-
vations of temperature and dew-point are not accessible.

5. The relation of tornado regions to thof^movement of
upper and lower clouds shows that the former indicate the
presence of the cold northwest current, and the latter the
warm southwest current of air, which ultimately lead to the

4/^

/ ^
/ a

1 //nrizon

Iw "§
\ ^

/ Ma/or ®

Iw ' is

I03

development of the high contrasts of temperature so essential
to the birth of tornadic action.

6. The study of the relations of tornado regions to the
form of barometric depressions shows that tornadoes are more
frequent when the major axis of the barometric trough trends
north and south or northeast and southwest, than when it
trends east and west.

ILLUSTRATION. SEE OPPOSITE PAGE.

The forms of barometric depression, as shown in diagrams
Nos. I and 2, are favorable to tornado development; those
shown in diagrams Nos. 3 and 4 are unfavorable to such de-
velopment. These facts should be carefully considered when
examination is made of the storm conditions as shown on the
daily weather-map of the Signal Service, which is now dis-
played in all of the principal cities of the country and is
placed in the hands of many private subscribers.

The following table, prepared by Prof H. A. Hazen, of the
Signal Service, presents very interesting and valuable informa-
tion concerning the relation of the region of tornadic action
to the position and intensity of the area of barometric mini-
mum or general storm-center.

The general average of this table gives the mean distance
of tornadic action from the 'Mow," or storm-center, as 453
miles. The mean direction is south 39° east. The mean
temperature fall is ten degrees in 259 miles. The winds are
almost uniformly from the south and southeast, and if from
any other quarter, all are from that direction. The distances
to the nearest north winds are variable, and in many instances
there were no north wijids on the map near the ''low ''or
near the tornado. The mean distance of north winds in
thirty-one cases was 407 miles.

I04

•eailonT

iiiiil ill i|i iiiaipi

•B9iTai ai oOT

>o »rt r/^ fvi r<i rri ^ ift r<i r<i >o >o »o !("' r*^ rTi

illiillillllltligl

Itei

CKilSKSBGlSEaKiSfe

I05

01 aoa^ieid

OOOOOOOOOOOOO • 'OOO 'OO

OkooooicoiooirtHiot-oocD ; :(Nocci :cth

rjH O lO iH CO t1< cocoes cocoon . .-^iXiCO .COtO

OQ H CQ f4 CQ ^ 02 02

•eQiTui m oOI

ooooooocooooooooooooooi
oocqd(M-<#(Mcooo:iocdoicOthO'^»ool^io

O (M t1< (M tH tH t> tHr-( rH tH 00 rH CO 03

CD O ®

^0202'

(MO

00©

CO(M(M

0000

00000

OiOOOtNCD
(Mrt^COCO

0202 ~^.aim<y^
^ 02

OOOOOOOCC

^ 03 (M CO CO CO (M 10
0300^0^ C3'^tJ<

a sa a a aaa

Ph fl ft P< d ^ d d d ^ d d ^ ^ d ^ ^ d d d
o ^00 ^.o ^. H Ro ^ *^oo ^.1000 ^ ^ H

CO ftCO-O C^rH ftP^ftCO ftftCO'* ft-^f^COCO ftftft
rHI>Ti5o4t>'^ COC^I>OCOTt<0 0iOQCOCO»OTHCOCO

x"^^o^coooco"co"co"coco"o''^"oo"•^">o"cD"o^o"o"^^

iHrH OQiHOQr-iO? rH rH tH tH 03 CO CO iH

^ ^ g g O ^ ^ g ^ j»

03 O O CO Oi 03 rH tH 00 0^ Oi Oi Ol O GO l> GO CO 00 1> O

03 tH t> CO O O O 03 CO CO Kt) C- 03 1> GO Oi 03 Ci CO Ti< 0^

c30

dHdd^ .
d^^-ga^M

|w o

Sh 05 o

oS)X

rt'^ <^ a

g TO (J) o

oTM o

g ^ ft®

io6

LIST OF TABLES GIVING CONDENSED INFORMA-
TIONS CONCERNING TORNADOES; GEO-
GRAPHICAL, FINANCIAL, CHRON-
OLOGICAL, DESCRIPTIVE, ETC.

The following tabulations present in a comprehensive and
concise manner the very foundation upon which the super-
structure of this work has been reared.

Tornado study as submitted in these pages was pursued by
inductive methods. Investigation was made in the field, subject
to all the inclemencies of the weather.

The tornado's peculiar formation and dreadful violence were
carefully observed and actually experienced, no effort or sacri-
fice being spared to secure the unvarnished facts without pre-
disposition to any theory.

We have then as the outcome of such methods of study, a
compendious summary of tornado observation and research,
which has been conducted unremittingly for the past ten years
and which will form the ground-work of all future investigation
into this class of meteorological phenomena.

The data used in these tables are matters of official record, but
their presentation and arrangement conform to the ideas of the
author and exhibit a classification which it is thought will best
serve for the information of those interested.

Table No. i. Total number of tornadoes observed, 1682 to
1886, inclusive.

Table No. 2. Violence of tornadoes ; relatively by States.

Table No. 3. Violence of tornadoes ; by States, including
loss of life and property.

Table No. 4^ Actual years of tornado records.

Table No. 5. Periods of development in different portions
of the country.

I07

Table No. 6. Tornado record of the last seventeen years.

Table No. 7. Time of occurrence, hour of day and night.

Table No. 8. Direction of progressive movement of the cloud.

Table No. 9. Form of tornado-cloud.

Table No. 10. Temperature before the tornado.

Table No. 11. Temperature after the tornado.

Table No. 12. Valuation of property destroyed; by States.

Table No. 13. Periods of observation; by States.

Table No. 14. Relative frequency ; by months.

Table No. 15. Relative frequency ; by States.

Table No. 16. Relative frequency; by months and States.

Table No. 17. Monthly frequency expressed in percentages;
by States.

Table No. 18. Relative frequency, days of the month.

Table No. 19. Combination table, maximum frequency, etc.

Table No. 20. Consideration of States by quarters.

Table No. 21. Relations of tornadoes to forests and cleared
land.

Table No. 22. Combination table ; occurrence by months,
States, etc.

Table No. 23. Hour of occurrence, months and States.

io8

Table No. 1.

A table showing the total number of Tornadoes observed in the United States
during a period of 205 years, from 1682 to 1886, inclusive.

Statks and Territories.

Missouri,

Kansas,

Georgia,

Illinois,

Iowa,

Alabama,

Ohio,

Indiana,

Minnesota,

Texas,

Michigan,

New York,

Pennsj'^lvania, .

Wisconsin,

North Cai olina,
South Carolina,

Nebraska,

Mississippi,

Dakota,

No. of
Storms.

156
153
128
127
118
102
92
84
78
73
71
67
61
59
59
57
52
49
46

States and Territories, j g^^jij^s

Arkansas,

Tennessee,

Kentucky,

Massachusetts,

Louisiana,

Virginia,

Maryland,

Connecticut,

New Jersey,

Florida,

New Hampshire,

Maine,

Indian Territory,

Vermont,

Colorado,

West Virginia

Rhode Island,

Delaware,

District of Columbia,.

34
31
26
22
19
18
16
13
12
10
8
7
6
4
4
2
1
1
1

Total number observed, 1,867

Table No. 2.

The Violence of Tornadoes expressed relatively by States in the order
named. By A^iolent in this sense is meant the most completely developed stoi ms,
with perfect conditions longest sustained.

States.

Missouri,

Iowa,

Alabama,

Arkansas,

Georgia,

South Carolina,

Wisconsin,

Minnesota,

North Carolina,

Michigan,

Dakota,

Kansas,

Illinois,

Nebraska,

Ohio,

Indiana,

Mississippi,

Texas,

New York,

Pennsylvania,

Kentucky,

Tennessee,

Virginia,

Massachusetts,

Indian Territory,

New Jersey,

Louisiana,

Connecticut,

Vermont,

Maryland,

New Hampshire,

Maine,

Khode Island,
Delawaie,
Colorado,
Florida,
West Virginia.

I09

Table No. 3.

Violence of Tornadoes by States, embracing the destruction of property,
reportedln definitely as "much," " great. " etc.; loss of life, reported definitely
and indefinitely : and numher of people wounded, reported definitely and
indefinitely.

Destruction
property.

Lives

Lost.

Persons
Injured.

STATES.

ery

ctive,"
cases.

uch

erty,"

cases.

Town
troyed,"
of cases.

ruction

at,"

cases.

c 2

CP ^

m
i-^

eral,"
cases.

dreds "
cases.

i-l

eral,"
cases.

P 6

^®
- 6

o o

■ o

dest

I iM O.

- CO .

" <v o

^ 6

Q !!;

" A

Alahama,

117

Arkansas,

229

Connecticut,

Dakota Ter.,

Delaware,

Florida,

"'6

'"6

G eorgia,

150

192

Illinois,

368

161

Indiana,

Indian Ter.,

Iowa,

175

424

Kansas,

204

Kentucky,

107

Louisiana,

Maryland,

Mass.

' 3

Michigan,

Minnesota,

164

567

Mississippi,

935

471

Missouri,

247

1050

Nebraska,

New Hamp.,

New Jersey,

lil

New York,

N. Carolina,

142

Ohio,

154

252

Penn.,

142

Rhode I 'Id.,

S. Carolina,

104

Tennessee,

Texas,

102

146

Vermont,

Virginia,

Wisconsin,

141

382

Totals,

233

384

3165

5049

Note.— This table is only approximate in its values, for in many cases of Torna-
do occurrence no reports could be obtained as to loss of life and injury to persons
and property. " Destruction of property" referred to in this table is entirely
independent of the money value given in table No. 5.

Table No. 4.

Actual years of tornado Records represented in the charts and tables.

1082

1804

1818

1830

1840

1850

1860

1869

1878

1728

1805

1819

1831

1841

1851

1861

1870

1879

1720

1807

1820

1832

1842

1852

1862

1871

1880

1761

1808

1821

1833

1843

1853

1863

1872 ■

1881

1787

1809

1822

1834

1844

1854

1864

1873

1882

1788

1810

1823

1835

1845

1855

1865

1874

1883

1791

1811

1824

1836

1846

1856

1866

1875

1884

1794

1814

1826

1837

1847

1857

1867

1876

1885

1795

1815

1827

1838

1848

1858

1868

1877

1886

1797

1816

1829

1839

1849

1859

Total uimilDer of years, Eighty-Seven.

Length of Period (1682-1886), Two hundred and five years.
The Tornado for 1682 occurred at New Haven, Conn., June 10, at 2 30 P. M.
and was exceedingly destructive.

Table No. 5.

Time of Tornado Development with respect to Region of Country.
Average results.

In considering tliis question the application of the rule is made in a general
sense, and a somewhat arbitrary geographical distribution of time over tliat
section of the United States east of the Rockj^ Mountains is matle. Tliere are
four periods of time, and therefore four separate regions of tor nadio action, which
are described as follows :—

First Period.— December to March, inclusive, comprising the region embraced
l)ythe following States: Virginia, North Carolina, South Carolina, Georgia,
Florida, Alabama, Mississipi)i, Tennessee, and Southern Kentucky.

Second Period.— April to .Tune, inclusive. Region : Texas, Louisiana, Arkan-
sas, Missouri, Kansas, Colorado, Iowa, Nebraska, Dakota, and Miunesota<>

Third Period.— June to August, incl-isive. Region: Wisconsin, Michigan,
Illinois, Indiana, Ohio, Northern Kentuckj-, Western Penusj^lvania, \Vestern
New York, and West Virginia.

Fourth period.— August to November, inclusive. Region: Maryland, Dela-
ware, New .Tersey, Eastern Pennsylvania, Eastern New York, and the New
England States.

Ill

Table No. 6.

Tornado Record of the Seventeen Years last past.

Year.

Storms.
Ot)served.

Year.

Storms.
Observed.

1879 .

1880 .

1881 .

1882 .

1883 .

1884 .

1885 .

1886 .

.137
-114
- 88
.161
.200
-136
.280

1870

1871 9

1872 13

1873 12

1874 21

1875 ---- 80

1876 66

1877 70

1878 81

Total number in seventeen years, 1566.

A comparison of the data presented in this tahle with that shown in Nos. 1 and
8, reveals the fact that over 80 per cent of the observed tornadoes belong to less
than 9 per cent of the length of period. This fact, combined with a cursory-
review of table No. 12, might lead one to the conclusion that tornadoes were on
the increase. This would certainly be erroneous, and for the following reasons :

1st. A careful study of tornado development and distribution, shows that there
are as many considerations to justify the belief that tornadoes were quite as
frequent a hundred years ago as now, and that this degree or frequency will not
be diminished for a hundred years to come.

2d. The means of observation and record for 1886 surpassed those of any other
year, because the Signal Service had greater facilities for collecting reports, and
the rapid growth of the conntry, with a greater zeal of the press, brought to
light many occurrences which, before, would have been lost sight of.

3d. A stady of tornado development and distribution appears to indicate that
there are periods of maximum occurrence, alternating with those of minimum
occurrence, but the truth of tlie supposition remains yet to be determined,
when more complete and extended records are obtainable.

4th. Tornado records are not yet sufficiently full and complete to permit the
deduction that they are or are not on the increase.

5th. The conditions, atmospheric,topogTaphical, and geographical,under which
tornadoes are peculiar to the United States, or certain sections of it, have
remamed the same for ages, and there is no likelihood of a change in this direc-
tion to prevent or increase the occurrence of tornadoes.

'P8AJ8S

-qo sia.iois
JO o >c li?;ox

112

Table No. 7

1,867

•yapjoD
. -a.i joa Qini;
JO -ox:

•sasBO JO -ox

CO ^ ^ o 1 ^ ^

Wfhiiii

IP ^ 1 f r ^ f f =

•S9SB0 JO -OX

1,039

TIME.

\. to 12.80 p.m.
111. to 1.00 "
' " 1.80 "
c u 2.00 '«
' " 2.80 "
' " 8.00 "
' 8.80 "
' " 4.00 "
' " 4.80 "
' " 5.00 "
' " 5.80 "
' " 0.00 "
' " 0.80 "
' " 7.00 "
' " 7.80 "
' " 8.00 "
' " 8.80 "
' " 9.00 "
' " 9.80 "
' " 10.00 "
' " 10.80 "
' " 11.00 "
' " 11.80 "
' " 12.00 mid

JO -OJSr

TIME.

Totals,

113

Table No. 8.

•p9AJOsqo

JO -o^ moj.

•pQp.IOOOJ
^Oa KOI^.39Jip

JO -ox

m m m xfi ^Ji m m m m

•sasEO JO -ojsj

CO 00 00

•sasBO JO -ojs^E

i-O CO

^ C<l O

(M O (v^

•89S^0 JO -o^ST

^ ^ J

^ ^ ^

t ^ ^

114

•paA.iasQo
eaopBiLiox
JO osL mo I

1,867

•papjoDOj

10 II UIJOJ

sasuo JO 'Oisi

00
lO

JO "OK

Ti^ Oq iH tH iH tH rH iH

) rmation.

"Whirlwind."

" Inverted funnel."

" Elephant's trunk."

" Ball."

"Whirl."

" Local Whirlwind."

"A grayish, fluffy J
mass." 5

"Immense dark )
whirling mass." S

"Large revolving ]
cloud sent fun- [
nel roots to the (
ground." )

•sasBO JO "Oisi

C CO CO rH tH iH iH tH tH

Formation.

"Balloon."

"Waterspout."

" Cylindrical."

" Pear."

"Twister."

" Huge Serpent."

" Dense rolling mass"

"Dense cloud of ^
scowling hlack- >
ness." )

"Two funnels small )
ends together." 5

•sas^O JO 'OK

T}<OrJlTHHr-lrH rH iH
(MiH

Formation.

" Inverted cone,"

" Cone."

"Serpent."

"Turnip."

"Hogshead."

"Heavy rolling."

"Dense rolling

"Streams, 20 in )
number." S

" Large masses, a
if white sprf
fell to the earth

•sasBO JO -OSL

I— 1 r-i Ti< iH iH iH tH iH iH rH
OOrH

1,003

Formation.

"Funnel."

" Hour-glass,".

"Basket."

"Acorn."

''Column. '

"Dark mass."

" Boiling cloud."

"Black circular cloud.

"Clouds rolled like a
barrel."

"A long streak like
a spout reaching
from bottom of
cloud to earth."

Totals.

saop^ajox
JO -OK mojL

•888^0 JO "O^

C^rHrHtHTHrH(>JrHrHrMiHC<lrHC<lrHrHrHiHC^t>tHrHCCrHC^rHrHrHOTHi-HrHrH^

oooooooooooooooooooooooooooooooooo
ooor^c<^clc^l(^lcocoT^^Tflo^Oloco^>c350000(^^'^l(^^»clClOco^>xoi»oo

X CO GO (X) GO 00 (X) 00 (» (X) 00 (X GO CO OO X (X) GO Oi 05 Oi Oi Oi Oi Oi Oi O: CS 05 o: o: Oi O tH

■sas-BO JO *ojsr

rHrHTHrHrHrHrHrHr^iHrHC<JrHrHTHrHrHHrHrHrHtHrHrHrHrHC^iHC<lC^iHrHiH

o o o o

ooooooooooooooooooooooooooooo
OC<J»OiOXXXOOOOOOOO(M<MC^^Tj<iOOiOiC<X>XXOO
(X><:o:DCDiXiOiXit>t>t>t>t>t>'Xit>L^I>L^t>t>l>l>t>t:^t>t>t>XX

■S88B0 JO -o isT

eas-BO JO -OK

JHiHrHrHrHrHrHOOiHrH

g I o
q © o

s □ ^

^ ^ o

02 P

O O

ft^«2'^
ft®

i P r fl". "-^ s

o ftb"t^4^

ii6

Table No. 11.

TEMPERATUKE AFTER THE TORNADO.

Condition.

coo;

Condition.

OfC

(Thermomet-

of C
uper
reco

rically.)

d o-^

" Cooler and cliilly."

*' Cooler (next day)."

( Nov., )
< next J>
/ morn S

66°

t April.)

-
1

" Chilly." .

8°

68°

"Cool."

188

" Cooler."

45°

(May.)

68°

(May.)

" Slightly cooler."
" Much cooler."

50°

(June.)

69°

(May.)

" Probably cooler."
"Cold."

123

54°

(April.)

70°

(July.)

"Very cold."

" Suddenly very cold.'

" Colder."

56°

(April.)

72°

(June.)

" Much colder."

56°

(June.)

73°

(Aug.)

" Gradually cooler."

"Gradually cold."
" Gradually cool."

58°

(May.)

75°

(July.)

" Gradually colder."

60°

(June.)

75°

(June.)

" Suddenly cooler."
" Suddenly cool."
" Suddenly cold."
" Suddenly cold(sno'w
after, next day)."

60°

(April.)

80°

(Oct.)

60°

(Aug.)

81°

(June.)

" Suddenly colder."

8
6

62°

(May.)

" No change."

" No decided change."
" No great change."

64°

(May.)

" Not much change."

65°

(June.)

" No sudden change."

" Warm."

65°

(Sept.)

" Intensely hot."

" Suddenly cool, tem-

66°

(Sept.)

perature falling sev-

eral degrees in a few
minutes. "

66°

(July.)

Totals,

565

1,270:1,867

117

Table No. 12.

Reporled Valuation of Property Destroyed by Tornadoes. The values
here given are in the main largely underestimated, owing to imperfection of re-
ports, and in many cases failure to give any mention of the loss. It is estimated
that these values give, on the average, about 10 per cent of the actual loss sus-
tained.

Length
of

Tornado
record in
years.

63
46
205
12
12
92
52
68
44
28
77
18
27
54
78
64

Valuation of
property
destroyed.

$142,000
535,000
272,000
540,000
2,500
600,000
675,000
787,000
1,553,000
520,000
25,000
120,000
2,000
20,000
50,000
226,400

Minnesota,

Mississippi

Missouri,

Nebraska,

N. Hampshire,

New Jersey,

New York,

North Carolina.

Ohio,

Pennsylvania,

South Carolina,

Tennessee,

Texas,

Vermont,

Virginia,

Wisconsin,

Length
of

Tornado
record in
years.

32
64
46
16
70
65
99
61
83
76
125
79
34
58
71
43

Table No. 13.

A table showing the period of observation and record of the occurrence of
Tornadoes for each State from which they have been reported. States arranged
alphabetically.

Alabama,

Arkansas,

Colorado,

Connecticut,

Dakota,

Florida,

(Jeorgia,

Illinois,

Indiana,

Iowa,

Kansas,

Kentucky,

Louisiana,

Maine,

Maryland,

Massachusetts,

Michigan,

1823 to 1886
1840 " 1886

1877 '
1682 '
18T5 '
1875 ■
1795 '
1835 '
1818 '
1843 '
1859 '
1810 '
1869
1860
1833
1809
1823

1886
1886
1886
1886
1886
1886
1886
1886
1886
1886
1886
1886
1886
1886
1886

No. of
Years.

63
46
10
205
12
12
92
52
68
44
28
77
18
27
54
78
64

Minnesota,

Mississippi,

Missouri,

Nebraska,

N. Hampshire,

New Jersey,

New York,

North Carolina,

Ohio,

Pennsylvania,
South Carolina,
Tennessee,
Texas,
Vermont,
Virginia,
West Virginia,
Wisconsin,

PERIOD.

1855 to 1886

1823 '

' 1886

1814 '

' 1886

1871 '

' 1886

1807 '

' 1886

1822 '

' 1886

1787 '

' 1886

1826 *

' 1886

1804 '

' 1886

1811 '

' 1886

1761 '

' 1886

125

1808 '

' 1886

1853 '

' 1886

1829 '

' 1886

1816 '

' 1886

1880 '

' 1886

1844 '

♦ 1886

ii8

Table No 14.

KELATivK Frequency of Tornadoes, by months.

No. of
Storms

MONTHS.

No. of
Storms

g Or-:
III

Total No. of
Toriuuloos
observed.

January,

JULY,

232

FEBRUARY,

August,

147

MARCH,

152

September,

114

ArRH>,

313

OCTOBER,

MAY,

339

NOVEMBER,

June,

285

December,

1,867

Table No. 15.

A table showing the relative frequency of Tornadoes by States according to
the area of each in square miles, and to the length of record of observations dur-
ing a period, in the total, of 205 years, from 1682 to 1886, inclusive.

Relative frequency in this table is expressed decimally in terms of the unit of
value for each State, which is taken, for convenience of comparison, at 10,000
square miles.

h of

record

rs.

1 num-
year
State.

o ®

hof

record

irs.

1 num-
year.
State.

iiimiber
vnv for
sq. miles.

STATES.

fcJDO O

STATES.

^ tj

Aiea in
10,000

O} f-f

Area in
10,000
mi

Tornad
in 5

S <y
> S ^

< iH

Alabama,

5.1

1.62

0.32

Minnesota,

8.4

2.44

0.29

Arkansas,

5.3

0.74

0.14

MississipiJi,

4.7

0.76

0.16

Colorado,

10.3

0.40

0.04

Missouri,

6.5

3.39

0.52

Connecticut,

0.5

205

0.06

0.12

Nebraska,

7.6

3.25

0.43

Dakota,

14.7

3.83

0.26

N. Hampshire

7.9

0.11

0.01

Florida,

5.4

0.83

0.15

New J ersey,

0.8

0.18

0.22

Georgia,

5.8

1.39

0.24

New York,

4.7

0.68

0.14

Illinois,

5.5

2.44

0.44

N. Carolina,

5.1

0.97

0.19

Indiana,

3.4

1.23

0.36

Ohio,

4.0

1.10

0.27

Iowa,

5.5

2 67

0.49

Pennsylvania

4.6

0.80

0.17

Kansas,

8.1

5.46

0.67

S. Carolina,

3.4

125

0.46

0.13

Kentucky,

4.0

0.34

0.08

Tennessee,

4.6

0.39

0.08

Louisiana,

4.1

1.05

0.26

Texas,

26.2

2.14

0.08

Maine,
Maryland,

2.9

0.26

0.09

Vermont,

0.9

0.06

0.07

1.1

0.30

0.27

Virginia,

4.0

0.25

0.06

Massachus'tts

0.8

0.28

0.35

W. Virginia,

2.4

0.28

0.12

Michigan,

5.6

1.10

0.20

Wisconsin,

5.4

1.37

0.25

119

Table No. 16.

MONTHLY TORNADO FREQUENCY.

TOTAL NUMBER OF TORNADOES FOR EACH

8TATE.

Month, by States.

Cases, mon
not repon

Total No
Tornado
per Stat

1 Jan.

Feb.

March.

April.

May.

1 June.

July.

Aug.

Sept.

Oct.

Dec.

Alabama,

102

Arkansas,

Colorado,

Connecticut,

Dakota Ty.,

Delaware,

Dist. of Colnmbia,

Florida,

Georgia,

128

Illinois,

127

Indiana,

Indian Ty.,

Iowa,

118

Kansas,

153

Kentucky,

Louisiana,

Maine,

Maryland,

Massachusetts,

Michigan,

Minnesota,
Mississippi,

Missouri.

156

Nebraska,

New Hampshire,

New Jersey,

New York,

North Carolina,

Ohio,

Pennsylvania,

Khode Island,

South Carolina,

Tennessee,

Texas,

Vermont,

Virginia,

West Virginia,

Wisconsin,

Totals,

152

313

339

285

232

147

114

1,867

I20

Table No. 17.

ClT ATT

Monthly frequency expressed in percent-
age OF TOTAL Number of Tornadoes

IN EACH STATE.

Month of
greatest fre-
quency,
per cent.

Jan.

Feb.

March.

April.

May.

June.

Sept.

Oct.

>
o

Dec. 1

Alabama,

Marcli.

Arkansas,

April.

Colorado,

May Jun

Connecticut,

July!

Dakota Ter.,

July.

Delaware,

100

August.

Dist. of Columbia,

100

August.

Florida,

2l)

Sept.

Georgia,

Men, Apr.

Illinois,

May.

Indiana,

May.

Indian Ter.,

May.

Iowa,

June.

Xansas,

May.

Kentucky,

March.

Louisiana,

April.

Maine,

July.

Maryland,

August.

Massachusetts,

July.

Michigan,

May.

Minnesota,

July.

Mississippi,

April.

Missouri,

May.

Nebraska,

June.

New Hampshire,

July.

New Jersey,

August.

New York,

July.

North Carolina,

ii)

March.

Ohio,

May.

Pennsylvania,

May, Aug.

Bhode Island,

100

August.

Soutli Carolina,

i^4

February

Tennessee,

April.

Texas,

June.

Vermont,

July.

Virginia,

July, Sep.

West \ irginia,

Apl,June.

Wisconsin,

July.

121

Table No. 18.

Kelative Frequency of toiinadoes.
Months— Days.

1-5

Feb.

March J

April.

May.

June.

July.

Aug.

Oct.

1st.

2(1.

3d.

4tli.

5tli.

6th.

7th.

8th.

2 .

9th.

10th.

11th.

12tli.

13th'.

14th.

15th

16th!

17th.

18th.

19th!

20th.

21st

2 2d.'

23d.

24th.

25th.

26th.

27th.

28th.

29th.

30th.

31st.

No. of

Days.

No. of

cases,

days
not

recorded.

No. of

Tornadoes

per

month.

152

313

339

285

232

147

114

Number of cases month not recorded, 51.
Total Number of Tornadoes observed, 1,867.

122

TABLE No. 19.

CONSIDERATION OF STATES liY QUARTERS.

N.E. Quarter

S. E. Quarter

S.W. Quarter

N.W. Quart'r

^1 .

STATE.

Number of
Years of
Tornado Recoi

Total Nurabe
of Tornadoes

1 Total Number i
of Tornadoes.

Total Number i
of Tornadoes. |

1 Total Nu
of Torn a

Month
greatest
quenc

Month
greatest
quenc;

Alabama.

102

April.

March.

Mh.Nov.

March.

Aikaiisas.

M^arch,

April.

Apiil.

Colorado.

May.

June.

Conn.

205

Jul., Sep.

Jun., Ag.

May, Jul.
Ag., Sep.

Dakota.

August.

July.

June.

Maich.

Delaware.

Aug.

D.Columbia.

Florida.

Sept.

July.

Ap.,May

Till

Georgia.

128

Feb.

March.

April.

Illinois.

127

May

Sept.

May.

Indiana.

Aug.

May.

Indian Ty.

May.
May.

May!

April.

Iowa.

118

June.

April.

June.

Kansas.

153

May.

June.

1 o
iz

April.

May.

Kentucky.

Mh., Jul.

March.

Dec.

Fb.,May.
Ag. Nov.

Louisiana.

Oc.,Nov.

April.

Oct.

Ap., Nov

Maine.

May, Jul.

July.

Maryland.

August.

Aug.

Fb., Ag.,
Sept.

July.

Mass.

August.

Jul., Ag.

July.

Micliigan.

Ap., Jun,
Sept.

April.

May.

Sep., Oct.

Minnesota.

Ap.,May

Jun., Ag.

Jnly.

Aug.
April.

Mississippi.

March.

April.

Missouri.

156

May.

April.

My., Jun

Nebraska.

Sept.

June.

My., Jun.

N. II amp.

Oct.

July.

New Jersey.

Oct.

Aug.

Jul., Ag.,
Sep., Nov

April.

New York.

August.

July.

N. Carolina.

August.

Feb.,Mh.
May.

March.

April.

Ohio.

June.

May.

Penn.

Oct.

Aug.

May.

Jun., Jul.

Khode Is,

Aug.

S. Carolina.

125

March.

April.

Fb., Apr.

March.

Tennessee.

Ap., Jun.

Fb., Ap.,
Nov.

April.

Texas.

June.

April,

April.

Vermont.

Ma., Jul.,
Aug.

July.

Virginia.

Sept.

July.

June.

.lune.

W. Virginia.

June.

April.

Wisconsin.

July.

Aug.

July.

Totals

2,129

1,867

504

470

463

430

123

NOTE.— In preparing table 19 (see opposite page), the data for each State was
carefully charted on a large county map. The State was then divided into foar
approximately equal portions, making four quarters denominated N. E., S. E.,
S. W., and N. W. quarters. The data for each was considered by itself in de-
termining the peculiar value of that section, and afterwards tlie four sections of
each State were tabulated and brought together in convenient form for compara-
tive study, as indicated on page 122.

Table No. 20.

Month.

Total number
of Tornadoes
per State.

-I-

o f2 fl

January..

2.75

Alabama 9

Georgia 4

Illinois 1

Mississippi 1

Ohio 2
Pennsylvania 1

Tennessee 1

Texas 2

1.12
.50
.12
.12
.25
.12
.12
.25

1885

1866
1869
1870
1883

FEBliUAKY..<

5.23

Alabama
Georgia
Illinois
Indiana
Iowa
Kentucky
Louisiana
Maryland
Michigan
Mississippi
Missouri
New York
No. Carolina 8
Ohio 6
So. Carolina 13
Tennessee 3

1.59
.06
.12
.12
.18
.12
.06
.06
.12
.24
.06
.47
.35
.76
.18

1805
1820
1854
1867
1868
1871
1882
1883

March .

152

6.04

Alabama
Arkansas
Dakota
Georgia
Illinois
Indiana
Iowa
Kansas
Kentucky
Louisiana
Mississippi 15
Missouri 5
New York 2
No. Carolina 14
Ohio 6
Pennsylvania 3
So. Carolina 11
Tennessee 3
Texas 4
Virginia 2
Wisconsin 1

1.08
.08
.08

1.20
.24
.28
.04
.16
.24
.04
.60
.20
.08
.56
.24
.12
.44
.12
.16
.08
.04

1884

1849

185

1855

1856

1857

1861

1863

1865

1871

1872

1874

124

Table No. 20 — Continued.

Month.

^ .' ^ ^ ? 6 ^
I— I ■y I— 1 c — s

Total nnmber
of Tornadoes
per State.

^ ? o ®

- E S

o P c
b S £

55 p

Begion of
Maximum
Frequeucy.

April.

34 313 9.21

Alabama 21
Arkansas 12
Dakota 5
Florida 1
Georgia 30
Illinois 15
Indiana 6
Indian Ter. 2
Iowa 31
Kansas 30
Louisiana 7
Michigan 11
Minnesota 16
Mississippi 19
Missouri 32
Nebraska
JSTew Jersey 1
No. Carolina 11
Obio
Pennsylvania 2
So. Carolina 12
Tennessee 10
Texas 22
Wesi Virginia 1
Wisconsin 2

.62
.35
.15
.03
.88
.44
.18
.06
.91
.88
.21
.32
.47
.56
.94
.24
.03
.32
.18
.06
.35
.29
.65
.03
.06

1886

1804
1819
1823
1827
1829
1830
1832
1833
1834
1837
1843
1852
1860
1865
1866
1873
1874

Iowa
and
Missouri.

May

35 339

9.40

Alabama
Arkansas

Colorado 2

Connecticut 1

Dakota 2

Florida 1

Georgia 8

Indian Ter. 1

Illinois 50

Indiana 25

Indian Ter. 3

Iowa 18

Kansas 45

Kentucky 3

Louisiana 1

Maine 1

Maryland 1

Michigan 14

Minnesota 4

Mississippi 8

Missouri 42

Nebraska 11
New Hamp. 1

New York 5
No. Carolina 3

Ohio 32

Penn. 13
So. Carolina 6

Tennessee 4

Texas 8

Vermont 1

Virginia 1

Wisconsin 7

.26
.26
.06
.03
.06
.03
.23
.03

1.43
.71
.11
.51

1.29
.09
.03
.03
.03
.40
.11
.23

1.20
.31
.03
.14
.09
.91
.37
.17
.11
.23
.03
.03
.20

1886

1761
1808
1809
1823
1831
1832
1834
1835
1837
1838
1839
1840
1854
1855
1860
1867
1870

125

Table No. 20. — Continued.

Month.

® C <Ii
<J as p

^ cdLj

Total iinmber
of Toi'iia loes
per State.

Region of
Maxmnim
Frequency.

285

-.91

July .

232

7.24

Arkansas

Colorado

Connecticut

Dakota

Georgia

Illinois

Indiana

Iowa

Kansas

Kentucky

Maryland

Mass.

Micliigan

Minnesota

Mississippi

Missouri

Nebraska

New Jersey

New York

No. Carolina

Ohio

Penn.

So. Carolina

Tennessee

Texas

Virginia

W. Virginia

Wisconsin

Arkansas

Connecticut

Dakota

Florida

Georgia

Illinois

Indiana

Iowa

Kansas

Kentucky

Louisiana

Maine

Maryland

Mass.

Michigan

Minnesota

Missouri

Nebraska

New Ham p.

New Jersey

is'ew ^ ork

No. Carolina

Ohio

Penn.

So. Carolina

Tennessee

Texas

Vermont

Virginia

Wisconsin

.06
.06
.06
.22
.11
.72
.36
1.03
1.11
.06
.03
.08
.22
.42
.03
.81
.50
.03
.22
.08
.42
.33
.03
.08
.72
.08
.03
.22

.09
.09
.44
.06
.22
.12
.28
.47
.56
.12
.03
.12
12
.28
.22
.62
.41
.19
.12
.06
.88
.09
.28
.28
.12
.03
.12
.06
.16
.59

1886

1682
1794
1829
1840
1841
1843
1845
1854
1855
1864
1865
1867
1869
1870
1872
1873

Kansas.

1884

1814
1816
1831
1834
1845
1850
1854
1861
1867
1870

New York.

126

Table No. 20. — Continued.

Montli.

Total number
of Tornadoes
per State.

o 5 n

OJ c c?

Region of
Maximum
Frequency.

147

4.19

3
11
1
1

5
7
1
3
8
2
1
6
5
5
17
1
5
2
1
3
9
4
6
13

Rhode Island 1
So. Carolina 2
Tennessee
Texas
Vermont
Virginia
Wisconsin

Connecticut
Dakota
Delaware
Dist. Col.
Illinois
Indiana
Indian Ter.
Iowa
Kansas
Kentucky
Maine
Maryland
Mass,
Michigan
Minnesota
Mississippi
Missouri
ISTebraska
New Hamp.
New Jersey
New York
No, Carolina
Ohio
Penn.

September.

20 114

5,71

Connecticut

Dakota

Florida

Georgia

Illinois

Indiana

Iowa

Kansas

Maryland

Mass.

Michigan

Minnesota

Missouri

Nebraska

New Hamp.

New Jersey

New York

No. Carolina

Ohio

Penn,

So, Carolina

Virginia

Wisconsin

.09
.31
.03
.03
.14
.20
.03
.09
.23
.06
.03
.17
.14
.14
.49
.03
.14
.06
.03
.09
.26
.11
.17
.37
.03
.06
.09
.14
.03
.06
.37

.10
.20
.15
.15
.75
.30
.15
.35
.05
.10
.75
.15
.40
.30
.05
.10
.35
.20
.20
.20
.20
.25
.25

1787
1818
1822
1823
1827
1834
1838
1843
1844
1852
1858
1859
1860
1862
1870
1879

1886

Minnesota

1811
1822
1845
1848
1857
1867
1872
1873
1876

Illinois
and
Michigan.

Table No. 20. —Continued.

Month.

Total number
of Tornadoes
per State.

Region of
Maximum
Frequency.

OCTOBER. . .

Arkansas

Connecticut

Florida

Georgia

Illinois

Indiana

Iowa

Louisiana

Maine

Maryland

Michigan

Minnesota

Missouii

Nebraska

New Hamp.

New Jersey

New York

No. ('arolina

Ohio

Pennsylvania 1
Wisconsin 2

.05
.05
.10
.10
.05
.15
.30
.10
.05
.05
.20
.05
.10
.05
.05
.10
.05
.20
.10
.05
.10

1883

1797
1824
1826
1833
1834
1835
1837
1844
18i7
1854
1872
1880

Iowa.

NOVEMBER.

3.96

Alabama

Arkansas

Florida

Georgia

Illinois

Indiana

Iowa

Kansas

Kentucky

Louisiana

Michigan

Minnesota

Mississippi

Missouri

New Jersey

New Yoi k

No. Carolina

Ohio

So. Carolina
Tennessee
Texas
Wisconsin

.64
.29
.07
.14
.43
.29
.14
.07
.14
.36
.14
.07
.07
.43
.07
.07
.07
.07
.07
.07
.14
.07

1885

18' 1
1870
1870
1875
1876
1882
1884

AlaDaraa.

December..

2. 70

Alabama 5
Georgia 5
Illinois 1
Indiana 1
Kentucky 1
Missouri 6
Nevada 1
No. Carolina 3
Oii^o 1
Pennsylvania 1
So. Carolina 1
Tennessee 1

.50
.50
.10
.10
.10
.60
.10
.30
.10
.10
.10
.10

1884

1864
1870
1878
1883

Missouri.

128

Table No. 21

«3

•\oN.T 1 ^o^ooiVd 1 A 1

ox'r-ro 1 1

1 II

1 1

CONSIDERED ]

•!jd8S 1 1 1

1 1 <N Td5

rHr-l

•Snv 1 1 1

1 1 oToo 6

iHCM

•vciur 1

co'io't-^ 1

1 Oi ©"rH

1 coco

•9nn_c

co'l- 1

r-lrH

'A
W
«

O GO 1

CCUl

'ludy

r-l <N 1:0 C<1 CO (M co'ic oi 1
iH i-l (N (N (M 1

U3CMC0'"'<tC0"iO~Qd 1
rHrHrHrHCqCM

•qojBM

rjTco't^ 0 tH (M iC CO'co'o'iM CO rji IC l> X 1
>-l 1-1 iH iH r-l rH CM (M (N C<l (N

oi 1

(M j

•qaa

(M'"co''»crGO~arTir:o'~a6 1

rH iH r-l r-l tH (M (M CM j

DA'

•u-er

rHCOOi 1
rHr-l(M 1

Hour of
greatest
frequency.

6 to 7 p.m.

7 to 8 p. m.
11 p.m. to
midnight.

3 to 4 p.m.

1 to 2 p.m.

5 to 6 p.m.

6 to 7 p.m.

7 to 8 p.m.

2 to 3 p.m.

6 to 7 p.m.

Montli
of great-
est fre.
quency.

March.

April.

May,
June.

July,
August.

Total
No of
Torna-
does.

CO
rH

STATE.

ALABAMA,

ARIZONA,

COLORADO,

CONNECTICUT,

Table No. 21. — Continued.

DATES OF OCCURRENCE, CONSIDERED BY MONTHS.

•oaa

•aon:

•JDO

OiO

, .

■SuY

•X[nr

•aun£

•qo^

•u^r

Hour of
greatest
frequency.

6 to 7 p.m.

|4 to 5 p.m.l

1 to 2 p.m.
3 to 4 p.m.

Month
of great-
est fre-
quency.

August.

^ ■

Marcli,
April.

III

STATE.

Dakota,

Delaware,

;

Georgia,

I30

Table No. 21. —Continued.

06 j

cc5 1
^ 1

y<
0

•AOK 1

tH 1

cxT^'co 1

"1»0 1

06 1

-rfkOOi 1

iHiH(M(M

Co'cOfM* 1
rH(M 1

CONSIDEl

•SnY 1

THr-((MC<l 1

oTco 1

iH 1

THC^'rjrcOCOt^^ 1

(M(M<M 1

;^
0

•ounr

(M OO'Tit t> 00 oTrH CO 05 1
tH r-l iH iH iH (M (M <^^

rH rH tH rH ?q (M CO |

ZDCOOC^ of r^ToO Oi 0"(N MlO CO t> oTo'rH 1
tH iH iH tH i-j r-t (N C<1 !N (N <M (M O^J :0 CO

x'^o^od

rr!

r-i fH iH !M C^J

ecu]

•ITjdY

"^(£01 1

tHiHiHC<l(M 1

T-lr-ICO 1

FES OF 0

cido"odo»o 1

iHrHCMCa 1

rlTdiO

•u^r

Hour of

greatest
frequency.

4 to 5 p.m.

5 to 6 p.m.

Montli
of great-
est fre-
quency.

May.

Maj

Ma;;

-Jo 3 m

Tot£
No. <
Ton

doef

rJH

STATE.

ILLINOIS,

INDIANA,

INDIAN TERRITORY,

Table No. 21. — Continued.

Datks of Occurrence, Considered hy Months.

'09a

AOK

•JOG

d Tji I> GO"t> GO'CO^O

•qa^^

Month
of fifreat-

est f re
quency.

1-5

Total
No. of
Torna-
does.

STATE.

KANSAS,

132

Table No. 21. — Continued.

•oea

r-iOi

BY MONl

co"q6

iH(M

•AOM

rH<M

RED

•:jdas

od'co'o"c<rco

r-l(MOq(M

DONSIDE]

•Snv

CO
iH

co"©

(NCO

CiCO

C0r)<iO

!M0iCDf-iO

OOrHjq'NCO

•ounr

r-l

tHrHCO

r-ir-i

c<i

CO X 0 rj^ 10 CO 10 1- rH
fH tH iH tH <M (M CO

CCURI

•IijdY

1 (M''t>oD"arcood 1 1 1
1 "^"^ 1 1 1

kOCOGO'iC
rHiH (M

TES OF 0

•qa^

;^ #

<
ft

Honr of

greatest
equency.

to 4 p.m.

to 5 p.m.

to 6 p.m.
to 7 p.m.

to 5 p.m.

to 6 p.m.

10 CD

»n

f great-
est fre-
uency.

April.

July.

August.

July.

May.

Total
No. of
Torna-
does.

0^
rH

CD
r-(

(M
(M

cc
H

STATE,

Kentucky,

LOUISIANA,

Maine,

MARYLAND,

Massachuse^

Michigan,

133

Table No. 21. — Continued.

•SH.

I ONI

•AOJsE

— > .

— ~

COCOTjrco"oi

DONSIDEl

'Sw^

•Ain£

rHCCt>C0rHiOCDr-IQ0

(MCOXOfNCOCDOQO
r-( rH iH rH (N

CE, (

•aunr

iH rH iH iH CM (M CO

iHC^COiCXINCOTjHiOCDt^XOiHO
iHrHr-lr-lrHr-trHCqOaCO

PS
PS

0
0

(MCO

IH1H

U50005i-iCOI>COOi©Tl<iX>XOiOTH
iH'-trHr-lrHC^(MC<>C<l(MCOCO

•ITjdY

l-tTH

iH r-( rH Cq C5 (M CO

iHQ0(MTl<00CO^COOi
iH iH tH (M !N <N

lES OF 0

OrH(NC0t>G0Ct>Q0

rHiH(M(MCO

r-Tco't^

<
P

Hour of

greatest
frequency.

3 to 4 p.m.

1 to 2 p.m.

5 to 6 p.m.

Month

of great-
est fre-
quency.

July.

April.

May.

Tota

QO
l>

CD
rH

STATE.

MINNESOTA,

MISSISSIPPI,

MISSOURI,

134

Table No. 21. — Continued.

•09a

•AON

'*das

'Sny

•Ainr

2§

•auui'

r^ TjH o'Cvi ^ sO 0 of ^ g

T-H

rHrHr-l(M

1
0

'lijdY

(M*

•WS£

4 to 5 p.m.

3 to 4 p.m.
5 to 6 p.m.

Month
of great-
est fre-
quency.

}

1-5

Total
No. of
Torna-
does,

STATE.

Nebraska,

NEW Hampshire,

NEW Jersey,

135

Table No. 21.— Continued.

Dates of Occurrence, Considered by Months.

■Aojsr 1 ^

+''0 1

-To

•Idas ^^'^

I— I (M

iHrHrHCO

rHr-i:0

r-lr-l(M

•9unr ^'i^

i-H IH r-l tH r-( (M (M

coiocot-iHcct-oD'-'ao

rH iH 1-1 T-1 (M !M CO

r-l(N

cod

tH ^

d"(M*

•qa^

i-ti-lfHi-t

Hour of

greatest
frequency.

S
ft

4 to 5 p.m.

5 to 6 p.m.

Vlonth
: great-
st fre-
uency.

March.

May,
ugust.

August.

Total
No. of
Torna-
does.

STATE.

NORTH CAROLINA,

OHIO,

W
Q
0

13^

Table No. 21. — Continued.

<N
<M

•AOM

tod

•:^das

•Snv

•jCinr

•9nnf

•lijdv

3 to 4 p.m.

1 to 2 p.m.
7 to 8 p.m.

4 to 5 p.m.

Month
of great-
est fre.
quency.

Total
No. of
Torna-

does.

STATE.

Tennessee,

Texas,

VERMONT,

137

Table No. 21. — Continued.

[ONT

•AOJsI

CE, CONSIDERED :

(M*
rH

did

<MCCr-ICOO»H(MOO
iHr-((N(N(M(M

ccoo"coV

r-lTH(MOq

•aunr

CO
iH

CCURREN

»H(N(NCO

CO
iH

FES OF 0

<
ft

'we£

Hour of
greatest
frequency.

4 to 5 p.m.

Month

of great-
est f re-
quency.

July.

Apl, Jun.

July.

0 0 s 0

STATE.

VIRGINIA,

WEST Virginia,

WISCONSIN,

138

Table No. 22.

Table showing the Relation of the Occurrence of Tornadoes to the
Acreage of Forests and Cultivated Lands, «y States.

o ^

c3 g o § r

O) ^-rS O CD 2^

Alabama,

Arkansas,

Colorarlo,

Connecticut,

Dakota Territory,

Delaware,

Florida,

Georgia,

Illinois,

Indiana,

Iowa,

Kansas,

Kentucky,

Louisiana,

Maine,

Maryland,

Massachusetts,

Michigan,

Minnesota,

Mississippi,

Missouii,

Nebraska,

New Hampshire,

New Jersey,

New York,

Noi th Carolina,

Ohio,

Pennsylvania,
Rhode Island,
South Carolina,
Tennessee,
Texas,
Vermont,
Virginia,
West Virginia,
Wisconsin,

1823 to 1886
1840 to 1886
1877 to 1886
1682 to 1886
1875 to 1886
1885 to 1886
1875 to 1886
1795 to 1886
1835 to 1886
1818 to 1886

1837 to 1886

1859 to 1886
1848 to 1886
1869 to 1886

1860 to 1886
1833 to 1886

1821 to 1886
1823 to 1886
1855 to 1886
1823 to 1886
1814 to 1886
1871 to 1886

1807 to 1886

1822 to 1886
1787 to 1886
1826 to 1886
1804 to 1886
1811 to 1886

1838 to 1886
1761 to 1886

1808 to 1886
1853 to 1886
1829 to 1886
1816 to 1886
1838 to 1886
1843 to 1886

102
34
4
13
46
1
10
128
127
84
118
153
26
19
7
16
22
71
78
49
156
52
8
12
67
59
92
61
1
57
31
73
4
18
2
59

•51,540
53,045
103.645

4,845
147,700

1,960
54,240
58,980
56,000
35,901
55,475
81,700
40,000
45,420
29,895
11,124

8,040
57,524
72.205
46;340
68,735
76,185

9,005

7,455
47,620
48,580
40,760
44,985

1,085
30,170
41,750
262,290

9,135
40,150
24,645
54,450

10,430,727
7,861,409
44,117
646,673
80,264
279,099
2,186,601
15,269,225
4,935,575
5,935,308
2,755,290
991,187
10,106,072
4,557,332
2,682,296
1,634,019
1,004,099
4,452,265
2,030,726
9,144,323
10,137,790
321,566
1,296,529
708,092
5,195,795
13,868,086
5,982,507
6,810,331
182,6<i6
7,255,121
11,232,876
15,851,365
1,503,467
9,126.601
6,180,350
4,768,046

139

. JO jaqranu yb^oJj

papjooaj 10U jnoq
pn-B TnnoTu '-OM iBjoj, I

•in L0%9\

'm •'B g 0% Q \ ^

•ui "B f o:^ 8 1

•ai -B 8 oa s 1

•ui -B g o:H 1

•ni -B X o:^ SI 1

•upiK 0!; XX 1 '~' '-I'-i'?^'-'

•m •(! XX 01 1 "^"^

•ra -d 01 0* 6 1

•ni -d 6 0^ 8 1

tH tH

•HI -d 8 o:^ 2, 1 CO (Mr-i

•in -d 2, 0!^ 9 1 (MrHCQ r^

rH rHrHrH

•ca "d 9 0!^ g j (MtHtHih

(M tH ' iH

•ut 'd s oc|. j ^

iH iH iH

•ui -d f 0!; 8 1 '"^'^

iHrH iH r-l

•m-d2 0iz\ '-''-"^

iH iHrH tH tH

•ni -d s o; X 1

•ni -d X 0^^ SI 1 '•^

•niSXOC^XTl ^

r-l

•ui-Btxo;oil ^

•ui-B0XOC^6l

•ni 'B 6 0(; 8 1

•ui -B 8 o:^ 2, I ^

•smnoin

r-lC^O? rM

State.

Alabama.

Total 93.
Arkansas

Total 33.

COLORADO

Total 4.

CONN.

Total 12.

Mod til

Jan. 1

Feb.

Mar.

Apr. ^•

May

Nov.

Dec. J

Mar. 1

Apr.

May

June

July

Oct.

Nov. j

May )
June 5

May 1
June 1
July (
Aug. '
Sept.
Oct.

I40

•poAjasqo e^opBTLiox
JO jaquinu i^ox

•in "B 1 o; 9 I

•oi "B 9 0^ e 1

f— (

'm-'B ^ (yif ]

'm'V20%z\

•ni "B 3 X 1

•HI I (X^ SI 1

rHrH

•npTH IT 1

r-l iH rH

•ra -d II (n OT 1

•tn -d 01 o; 6 1

»H

•ni -d 6 <n 8 1 "-^

tHiH

•HI -d 8 1

CCrHCO

•DI-d2,0{^9| iHCOCCiH rH

»0 »-ItH

•ni-d9 0is 1 "^^^

•lU'dgO^T^l iHrHfH rHrH

CO iHtH

•ra -d t o:^ g 1 <^''-' ^

rJ<0O<MrH

•ra -d 8 o:^ S 1

COiHiH tH

•ra •d g 0^ I 1 "-^^ »-<

rj4CCr-lTH rH

•ra -d I 0^ 51 1

COCOiH

•ra 51 o:ni 1 >h

•ra 'B II 01 1

r-i r-i

•ra 01 6 1

•ra •« 6 8 1

•ra --e 8 o:^ i I

•emnora

5 ^ g

1-5 ©

141

JO jaqrarm i«!^ox

pn^ it^^noni ' ok T'^^oJi I

•ni 9 o^ e I

•UI "B f 0^ 8 1

•TO "B s o^x 1

r-i

•ni "B I o:^ 51 1

r-i

•upipi o:ni 1

-m -d IX o; OT 1

•ra a 01 6 1

•in -d 6 o:^ 8 1

CCiH

rH(M tHiH

'm'6.so%i\

rHW <MrHrH

COiH rH

•ni -d 9 o:^ S

»H(MCO(M r-liHr-l

(M tJ<tH(MiH

•in 'd Q o:^ f

CCGOCCiH iH

»OtH iHiHtHiH

•UI 'd 8 O;^ g I THiHrHrHlMrH

'm'dz(ni\

(MiH

■m -d X o:^ sx 1

•ni zi 0% XT 1

•ni •'B XT 0^ OT 1

•m --B OT 0!; 6 1

•ni •'B 6 o:^ 8 1

•in "B 8 A 1

•STunoni

142

JO jaqrana inxoj, \

•papjoDOJ jou jnoi{

'ui 'IS Q 0% q \

•m "B <^ o'Xf \

•UI t g 1

tH ,Ht-I

•in -^£0%^ I

•UI 'T3 I o:^ 3X 1

•npTM o; XI 1

r-l tH r-l

•m a II o; 01 1

iH r-l tH

•in -d 01 o; 6 1

(MtH

•ni •(! 6 0^ 8 1

CC <MrH

rH iH tH

•ni 'dso% I i

•lu -d 0^ 9 1

iHiH tH iH

•ni •(! 9 o(j Q 1

•in •d e 0^ t 1

tXMlOCO i-HrH

(M CO CO O O rH-

•ni •d ^ 01 8 1

:0XlOrHrHrH CO' i-irH

•in •d 2 0%z\

(NiHrH (M

H^ rH iH rH- rH

•ni •d s 0!H 1

tH tHiH

rHrH rH rH

•ni -d I 01 SI 1

r-t <M

rHCq

•UI 51 01 II 1

•in '13 II 01 01 1

CO rH

•ni "B 01 01 6 1

rH (N

•ni •« 6 oi 8 I

•m •« 8 01 L I

•sqinoin

pH<i^Hj.h,-<a20 ^<i^i-5^-j<iaj

143

•p9AJoeqo saop^njox
JO .laqranu i^c^ox

pap.1008 J ^jou .mot[

•ni "B 2, o:^ 9 1

•ni 9 0^ 2 1

o
<J

'm ^ 0!; g

•ra "e zoii

-m •'B I o:^ 51 1

•npiK 0^ IX

•ni -a 110% 01

•ra -d 01 o; 6

r-liH

•ra •(! 6 o:^ 8 1

•ra -d 8 2.

•ra •<! I 0% 9

tHiH rHiH rH rH

MB!

•ra 'dQo%Q

rH (MrH r-{r-(r-i CO <M rH

•ra •(! 2 t

rHrH Cq CO rH rHC^rH r-ir-i (MrH rH

•ra •d f o; 8

rH rH rH r-ir-i CO rH

•ra •d 8 0!; 5

rH(?q rH

•ra •d s 01 X

(MrH rHrH

•ra •d X o:^ zi

R OF OCC

•ra zi 0% XX

rH ■ rH (M

•ra "B XX 0% OT

•ra •'B OX o:^ 6

no:

•ra •'B 6 0^ 8 1

•ra •'B 8 01 ^ 1

C<It>rH<M»A TfTHrH rH rH r}< CO rH tH C005lO(M rH Tj< GO l> CO IC !M

rHrH rH

State.

go^o ^ o ^ o u ^

Montli

144

JO jaqrana t«40X

•pap.iooaj jon jnoq 1
pm? innoui 'OK leiojj \

CCi
(M

-m v 9 o; c I

•m "B =^ o; g I

•lu "B 8 oj s I

•in "B s o^ I I

•ra "B io%zi\

•lu 'd II o; OT I

•in -d 01 o:^ 6 I

•in -d 6 8 I

•oi -d 8 I

•ni 'd 2j 9 I ^

•ni •d 9 o; s

•OI -d g o:^ t rMccccrn

•ni •d o:^ g I 00 iho

•in •d g o^ S I

•m -d I o) zi I

•ni SI o^ II 1

•in II o:^ 01 I

•in •« 01 6 I

•m •'B 8 I

•ginuoin
joqninN iBiox

144^

•p9AJ9sqo eaop-enjox
JO jaqratin I'B'^oj,

10 tH CO

•papjooaj %on jnoq
pn« H(jnoni *'ojs[ 1'B!^ox

(M CO

•ni "B 2; o:^ 9 1

•ni "e Q(yxQ

'm ''B Q 0%f

•ni "B 8 o:^ g 1

-m s 0* T i

•ni "6 io%zi\

•npipi 0^ XI 1

•in -d XX 0^ OT 1

•ni -d 01 0!^ 6 1

•ni -d 6 0^ 8 1

r-l tH

•ui -d 8 0!^ 2, 1

rH rH

iHiHtHtH tH

•ni -d 9 o:^ Q

(M »H tH tH tHjH rH

•ni -6.^0% f

tHiHCOtH rH rH <M rH

•ni -d f 0!j 8 i

CO (MrH iH rH rHrH(rq rH

•ra -d 8 oc^ g 1

(M ' rH <M <M rH ■

•ni -d s o:^ X 1

T-ir-i rH rHrH CO

HI -d X 01 sx 1

OCC

•in zi o% XX

rH 0

•in "B XX 0% 01

•ui "B OT 0; 6 1

•ni -B 6 o:^ 8 I

•ni "B 8 o:^ 1

•smnoni

aiHQ0CO(MCOrH -^rH rHrHC^COC^fM (M lO X CXi 05 1> rH rH
rHrH (M

1 1 - § -

g |wl ^ 1 ^ 1

Month

144^

JO joqranu i^^oj,

paw ii;uoni '-ox I^^ox I

•ui 9 g I

•ni g o; 1 1

•ui foi2\

•lu •'B t OJ ST 1

'npiK o:ni 1 ^

r-t CO

•ra-d II 01 OT 1 '^'^

C5 rH

•ra -d OT 6 1 ^ ^

•ni -d 6 01 8 1 ^

•m d 8 01 1 1 ^

tHC<1 t-l rH

•UI -d 2; 01 9 1 <M'-' <-!

iHrH (M rH

•in 'd 9 01 g j ih (Nih t>»H tHiHih

•ra -d g 01 f 1

•ra •d t 01 p I '-<

•ra -d 8 Ol S 1 fHrHjq rHrH.H

•ra d s oi I 1

rH rH ■

•ra •d I 01 SI 1

•ra SI 01 III rH rH ,H

•ra •« II 01 OT 1

rH rH

•ra •'B 01 oi 6 1

•lu •« 6 01 8 1

•ra •'B 8 oi i I

•eqinora xri^^cocc:^
jeqranx I^iox '-^'-i

1 1 1 1 1

liillllfeii jiilillllii liilllli

144 c

JO joqninii i^^joj.

•popjoooj ion jnoT[
pm3 mnoai '-o^ i^io j, j

•in •'B o:^ 9 I

•ni 9 s 1

•in e 1

•ni •'8 f 8 1

•ui "B 8 s 1

'm."^Z^% \ \

•ni "B I o; SI 1

•npTivE o:ni 1

•UI •(! XI 0^^ OT !

•UI -d 01 6 1

iH tH

tHtH

•UI •(! 6 8 I

•UI -d g o:^ 2, 1

iH (MtH

•tu -d 2, o:^ 9 1

THrHCO

•UI •d 9 o:^ c 1

COCO ' rH

CO (M iH

•UI •d s 0^^ =1^ 1

iHtH CD rH i-H

•UI -d f 0^ 8 1 ^

COCQ-^ r-l

r-l x^T— 1

•UI "d 8 S 1

•UI •d 3 o:H 1

I— 1 >-(tH

•UI •d I o; 51 1

•UI z\ II 1

•UI •'B II 0!^ 01 1

•UI •'B 01 o:^ 6 1

•lu •'B 6 0^ 8 1

•UI •^ 8 L I

•sinuoui
iCq jaquini^ l^^ox

COiHCqO-^'^iHrH COC'^COTH^trH

o o

H Pi

.9^

§ 1 2

^ ^^^s^^!^' dii^'bs^^

<1 ^<J^55<t5^

144^

JO jaquinu i^ox

•ui -t? L(y^9\

•ui -B 9 s 1

•UI -v e o; f- 1

•lU -B 8 S 1 rH

•UI "B s (ni 1

•UI "B I o:^ SI 1

•upTH o; IX 1

•UI 'd XX o:^ 01 1

•UI •d 01 o:^ 6 1

•UI •(! 6 o:^ 8 1

(M-H iH

•UI •(! 8 o:^ 2. 1

•UI -d 2, 9 1

iH tHiH

•UI •(! 9 0^ e 1

iH iH

iH tH<MtHiH (M<M

•UI •(! 8 0^ S 1

COiH

'UI -d g 0^^ X 1

rHfH

•lu •d X 0^ sx 1

tH(M

•UI zi o; XI 1

tHiH iH

•lu --B XT o:^ OT 1

•UI •'B OX <n 6 1

•UI "B 8 o; L I

•STl^^UOUI

rH (M t> OO CO IC rH

RESULTS FROM TORNADO RECORDS
OP 205 YEARS.

1, The rotary movement of the whirling tornado-cloud is in
five hundred and twenty cases reported as against the hands of
a clock, and twenty-nine cases as probably moving with the
hands of a clock.

2. Electrical discharges were observed in two hundred and
fifty-two cases as occurrring in the clouds surrounding the tor-
nado-cloud ; that is, in the clouds near the horizon : and in
eighty-four cases as occurring in the funnel cloudc

3c The width of the path of destruction^ supposed to embrace
the distance between the areas of sensible winds on the two
sides of the tornado- cloud, varied in 1,167 cases from 10 to
10,560 feet, the average being 1,369 feet,

4c The length of the tornado's track, as reported in 385
cases, varied from 300 yards to 300 miles, the average being
24.79 niiles.

5. The velocity of progression of the tornado-cloud, as deter-
mined from the reports in 201 cases, varied from seven to 100
miles per hour, the average being 44. 13 miles.

6. The shortest time occupied by the tornado-cloud in pass-
ing a given point, varied from ^* an instant " to about twenty
minutes; the average being about seventy-four seconds.

7e The occurrence of thunder-storms in relation to tornadoes
is reported upon as follows : In 287 cases they occurred before
the tornado-cloud appeared; in 113 cases, accompanying the
tornado-cloud; in 57 cases, after the disappearance of the
cloud, and in eight cases their entire absence was noted.

8. Concerning the time of occurrence of the tornadoes, the
hours of greatest frequency are found to be from 3:30 to 4:00
P. Me and from 4:30 to 5:00 p. M.

9. The State in which the greatest number of tornadoes
occurred is Missouri, followed next in order by Kansas and
Georgia.

146

10. The month in which the largest number of tornadoes
occurred is May, followed next in order by April and June.

11. The month of greatest frequency, that is, the month
embracing the largest number of days on which tornadoes
occurred, is May.

12. The prevailing direction of progressive movement of the
tornado-cloud is northeast.

13. Of 990 cases where the time of rain was recorded, 377
reported precipitation as preceding the tornado ; 437 as follow-
ing it; and 176 as accompanying it.

14. Of 604 cases where the time of hail was recorded, 317
reported the precipitation as preceding the tornado; 124 as
following it; and 163 as accompanying it.

147

A SCIENTIFIC RESUMI3 OF TORNADO
CHARACTERISTICS.

What follows under the head of "Scientific Resume of
Tornado Characteristics, " was prepared for a special purpose
after much investigation and careful study.

What is called the "Electrical Origin of Tornadoes/' and
all violent local storms of a similar character, is not of recent
designation. Certain French scientists, foremost of whom
probably stands M. Peltier, whose first writings on this sub-
ject appeared in 1839, have asserted that all the usual phe-
nomena which combine to form whirlwinds are the direct
result of electricity.

In about i860, M. De Fonville, a member of the French
Academy of Sciences, discussed the electrical origin of storms.
The electrical theory has found many followers in America,
probably the most prominent in a sensational way being Prof.
Tice, the "Weather Prophet," of St. Louis, now deceased.

On the loth of June, 1879, ^ terrific storm of wind, rain,
and hail, moving from northwest to southeast, passed over
Ottawa Co., Kansas, nearly destroying the town of Delphos
in that county. Thirty-seven buildings were torn to pieces
and sixteen persons seriously injured. I visited the town
a few days after the storm and made a careful examination of its
path and the destructive effects. Prof Tice heard of this storm
through the newspapers, and, in support of his theory, pub-
lished in the Cincinnati Inquirer of June 5th, 1880, a long
article, from which the following extracts are taken : —

T hold that electricity is the cause of all meteorological phenomena,
winds of every kind, cyclones, cloud formation, rain, hail, and snow.

Railroad and telegraph lines obey the laws of induction and give rise
to the necessary electric changes to produce storms.

148

Have the following facts any significance ? Delphos, in Ottawa Co. ,

Kansas, is situated on the east bank of the Solomon River, and is a
station on the Solomon Valley Railroad.

A tornado on May 30th, 1879, destroyed the railroad depot and many
houses. The town was visited by a second and very destructive tornado
on the 6th of June, that is two tornadoes in eight days.

In this hasty attempt to bolster up a theory the calculation
missed its aim through discrepancies in the facts as follows :

1st. The tornado of May 30th, 1879, passed eastward three
miles southeast of Delphos without producing the slighest in-
jury in the town.

2d. The storm which struck Delphos occurred June loth,
and not June 6th.

3d. There was no railroad at Delphos, no railroad build-
ings, and no telegraph lines, but the people were trying to
raise the funds to obtain such conveniences by extending the
track, which then terminated at Minneapolis, about twenty
miles distant.

In 1879, '80, and' 81 the question of the electrical origin of
wind-storms came before the courts of certain States, princi-
pally Wisconsin, Missouri and Kansas, in the interest of
insurance claimants. Certain parties who were policy-holders
had their property (which was insured against lightning) de-
stroyed by wind-storms, and brought suit for recovery against
the insurance companies on the ground that, both in the
popular acceptation of the term and in its true scientific mean-
ing, lightning or electricity was the cause of all violent wind-
storms. This theory the policy-holders tried to maintain by
every possible means, and in the course of the struggle I was
summoned to appear before the courts as a scientific expert
on the question of the origin and development of tornadoes.
I made special preparation for the engagement, and took
occasion to embody the results of my labors in the form in
which they here appear under the heading of Scientific
Resume of Tornado Characteristics/'

149

In regard to the electrical origin of tornadoes, I take pleasure
in quoting from the pen of Prof James C. Watson, the great
astronomer and physicist, who at the time of making this
statement was director of Washburn Observatory, Madison,
Wis., and on the witness stand in one of the above cases.
He says : ' ' I think that all science that is science, proves
absolutely that the effect could not have been produced
by lightning. The force of the tornado cannot be explained
on the theory of electric action; it is utterly impossible, incon-
ceivable, and contrary to every well-established law of elec-
tricity.''

A SCIENTIFIC RESUME OF TORNADO CHARACTERISTICS.

1 . The forces of the tornado-cloud are active and continuous
while the phenomenon exists.

2. They are exerted successively, uninterruptedly, and always
in the same general directions.

3. The forces appear to be uniform.

4. The forces are not apparently diminished by having to
destroy a succession of the heaviest and strongest structures.

5. The forces are not affected by having to meet with, in
rapid succession, totally different objects — different in size,
strength, shape, materials, composition and structure, relative
position, etc., etc.

6. The forces are exerted continuously over a breadth of sur-
face varying from 50 to 600 yards. ^

7. The forces are exerted continuously for distances varying
from five to 200 miles.

8. The characteristics of the tornado-cloud are constant, and
all of its features and mode of development show it to be a wind-
storm, simply.

9. When the cloud disappears, it does so from the earth up-
wards, its action evidently depending upon forces in the upper
regions of the atmosphere.

10. The time of day, the time of year, and the peculiar hot
and stifling condition of the atmosphere indicate that heat is the
physical agent developing the tornado.

I50

11. The tornado is invariably accompanied by hail, which is
evidently not of electrical formation.

12. Electricity is simply an accompaniment of the tornado,
as is the hail, and not the primary cause.

13. The cloud is almost invariably funnel-shaped, with the
small end nearest the earth. The resistance of the atmosphere
is less at higher altitudes because of less density, consequently
the cloud spreads out at the top.

14. The tornado-cloud always has a rotary motion, from right
to left.

15. It moves in a certain direction, S.W. to N. E., without
regard to obstacles.

16. The tornado-cloud is generally impenetrable to vision,
and is sometimes dark, like coal smoke, and then again white,
like steam.

17. The contrast between the white, steam-like appearance
of the tornado-cloud and the surrounding dark clouds gives rise
to the semblance of fire, and the cloud appears illuminated.

18. What is called lightning by the frightened observers is
never seen by them when the tornado-cloud is observed in ad-
vance of the dark clouds to the westward and surrounded by a
clear sky.

19. What is termed the smell of sulphur" is simply ozone
in the air, which nearly always appears after a thunder-storm.

20. It is to be noted that a calm, cool observer rarely reports
the appearance of lightning in the tornado-cloud proper.

21. It i§. to be noted that lightning is always observed

and after the tornado-cloud appears, but in the heavy, dark
clouds far to the west, north, and northeast of the tornado cloud.

22. Observers are nearly always mistaken about the distance
of the flash of lightning. Light travels with inconceivable ra-
pidity, so does the electric fluid, and the electric flash is of in-
tense brilliancy, consequently lightning appears much nearer to
the observer than it really is.

23. Observers can really give no reason for their belief that
electricity is the cause of the tornado, but almost invariably
reply to the question, *'that if electricity is not the cause, they
have no idea what could produce such a terrible foi ce."

151

24- From an examination of a great many witnesses it is evi-
dent that the reason for behef in electricity as the cause is the
sudden, awful, irresistible, and terribly destructive force of the
tornado. It is of the air, wild and majestic, yet mysterious.

25. Many witnesses at first report the lightning as appearing
in the tornado-cloud, and then after careful thought remember
that the flashes were really from clouds far beyond the tornado-
cloud.

26. Almost invariably the observer is so placed that the
tornado-cloud is between him and the dark, threatening clouds
to the westward, so that in the excitement of the occasion he
cannot distinguish the exact location of the source.

27. In the tornado's track the debris is always carried in the
direction of the moving force, frequently in the arc of and some-
times entirely throughout a circle. This is not a peculiarity of
electric force.

28. Heavy and light objects are transported long distances,
the latter sometimes 50 miles.

29. Objects that are carried long distances are always trans-
ported to the east or northeast, and evidently by air-currents.

30. Objects carried long distances are frequently found unin-
jured.

31. Vegetation is withered by the action of the sun's heat in
evaporating the fluids from the leaves and buds that have been
broken and bruised by the whirling action of the air in the
tornado-cloud. The evaporation drys and withers the foliage,
and it looks seared.

32. Where the bark of trees has been chipped ofl" or loosened
in places the sap appears and is evaporated by the action of the
sun's heat, and as a result the tender surface of the exposed
portion of the body of the tree is turned black.

33. No ordinary wind or hardly a heavy, straight wind is able
to so whip the foliage of trees, or the leaves of grain and plants,
as to cause them to wither and appear scorched. It requires
the rapid, peculiar, and irresistible rotary action of the air in a
tornado to accomplish this result.

34. The energy of the tornado is exhibited with no greater
force in relation to metals than in relation to other substances.

152

35' The force of the tornado-cloud is not measured any
respect by the character of the materials upon which it acts.

36. The form of an object, no matter what the size, does not
control or modify or influence in any way the intensity of the
tornado's force.

37. Objects are destroyed by the peculiar force of the tornado
before the tornado-cloud reaches them. Trees begin to sway
and are bent to the ground, and buildings and lighter objects
are drawn or sucked towards the advancing cloud from all sides
of it.

38. By the rotary action of the tornado-cloud the condensed
vapor is whirled into a fine mist, giving it the appearance of
steam, and lighting the interior of the cloud.

39. The tornado is accompanied by a rumbling noise (very
peculiar), which never ceases while the funnel-shaped cloud is
upon the earth or a short distance above it.

40. Timbers acted upon by the force of the tornado are often
driven to considerable depths into the solid earth, sometimes to
the distance of nine feet. They are sometimes driven into build-
ings and other pieces of timber.

41. Wherever fire is reported to have been seen in the debris
of the tornado it has, upon close examination, been found that
witnesses did not actually see fire (they saw light) ; but they saw
smoke, and from that judged that fire must be present. Now,
this so-called smoke is nothing but the dust and condensed
vapor of the whirling tornado cloud, which envelops and pene-
trates every structure over which the tornado passes. This so-
called smoke is often seen issuing from the doors, windows, and
other openings of the house, and even out of chimneys, when
fire was known not to have been in the house at the time.

42. The energy of the tornado-cloud is confined with in very
narrow limits, the boundaries being distinguished with remark-
able exactness even in the atmosphere.

43. The width of the tornado's path upon the earth's surface
is probably the counterpart of the diameter of the upper or broad
end of the funnel-shaped cloud.

44. In the ricochet motion of the tornado-cloud, especially
as the cloud leaves the earth, the maximum destructive force is

153

found to be diminished, but not entirely suspended. The in-
rushing air-currents are still sufficiently powerful to overturn
fences, small buildings, and trees, and lift loose objects from the
earth.

45. In the ricochet motion of the tornado-cloud the cloud
does not dip down to the earth, although it appears to do so.
There is not an actual descent of the entire body of air within
which the terrible forces are at play. On the contrary, the in-
rushing air-currents from the earth's surface, as they pass upward
and unite with the disturbed conditions above, carry up dust and
small debris, which, mingling with the condensed vapor from
the rapidly rising air forms a dark cloud, and completes the con-
nection to the eye between the upper cloud and the earth.

46. The potential and living energies of the tornado must be
distinguished from the cloud, which simply shadows forth the
limits within which these energies exist or may be called into
action.

47. The so-called quiverings and contortions of the cloud are
but the peculiar movements, in fantastic forms, assumed by the
rapidly condensing masses of vapor.

48. The funnel form of the cloud is due to the peculiar
ascensional movement of air-currents, the vapor being condensed
along the central line of movement by the cold of elevation.
This action would tend to form a column of cloud, the upper
extremity of which would be broader than the lower, because of
the overflow and spreading out of the ascending masses of air
in the upper regions of the atmosphere, and also diminished
resistance to the gyratory motion of the vortex,

49. The motive power of a tornado and the agency which
lifts objects or carries them long distances, is that motion of the
air within the cloud set up by the variable heat conditions of
large masses of air over adjacent regions.

50. The violent upheaval of a small column of air forms a
vortex along the central line of movement within which the
power of pressure against all resistance is often greater than one
atmosphere.

5 1 . The tornado vortex may be formed either by an ascen-
sional movement of a mass of heated air, giving rise to unstable

154

equilibrium, or by the meeting of opposite currents with high-
temperature gradients, or by a combination of both of these
meteorological conditions.

52. Two currents of air approaching each other from oppo-
site directions will not come directly together, because of the
influence of the relative motion of the earth. The mass of air
coming from the south would have a greater velocity eastward
than that coming from the north. Therefore, instead of meet-
ing each other in a direct line, the two currents will form an
angle at their intersection, and the combination of the two
masses will give rise to a rotation in a direction contrary to the
hands of a watch with its face upwards. These conditions ac-
count for the spiral movement of the air-currents and the forma-
tion of the vortex in the tornado. The cold air from the north-
ward will under -run the warmer air from the southward, because
of the difference in density of the two masses, and as a result
will aid in the formation of the whirl.

53. The tornado vortex cannot remain stationary on the sur-
face of the rotating earth, but must, by well-known dynamical
laws, move bodily in a direction the resultant of the opposing
forces in its formation.

54. The tornado vortex will have a tendency to drift with
any strongly prevailing current of air.

55. The tornado vortex may be very whimsical in short move-
ments, owing to the extreme elasticity of air and the mobility of
its particles.

56. After carefully reading my various papers on the subject
of tornadoes, H. H. Rowland, Professor of Physics, Johns Hop-
kins University, Baltimore, says : " It becomes apparent that if
electricity has anything to do with the development of a tornado,
it is 7iot with the tornado-cloud itself after it has foriiied and the
tornado is advancing over its path of destruction, but with the
two clouds which attend the for77iation of the tornado."

57. All of the phenomena of a tornado cannot be accounted
for on the supposition of opposite electrification of two clouds.

58. According to Sir William Thomson, the electrostatic ten-
sion of air is only equal to a pressure of 68 grammes per square

155

decimetre, or one fifteen-thousandth of the pressure of one at-
mosphere.

59. There is no fact in observation or in electrical science to
prove that clouds, under any conditions, actually move about in
the atmosphere through the agency of opposite electricities or
electrical attraction.

60. In the incipient stages of a tornado, observers -always speak
of the rushing together of clouds from opposite directions. This
is a very natural and necessary effect in the development of a
vortex. It is the air-currents (set in motion by contrary heat
conditions) which cause the clouds to move, and not electrical
attraction.

61. There is no distinction between the movements of air
masses under the most ordinary atmospheric conditions and
those under which they move in the tornado, except in intensity.

62. If electrical attraction is the cause of air-motion in a tor-
nado, it is the cause of any and all atmospheric movements,
however feeble or mighty. But this remarkable position no
physicist contends for a moment.

63. The electrical tension of the air cannot under the most
favorable atmospheric conditions cause the movement of oppo-
sitely electrified air masses, because of the excellent conductivity
of free air, which always tends to equalize electrical potential.

64. In a mass of air or cloud having an altitude of one mile,
a diameter of one mile, and a thickness of one-tenth of a mile,
the electro-motive power can never exceed 68 grammes per
square decimetre. Converted into English measures this expres-
sion denotes a pressure of 1,049.3964 grains upon an area expos-
ing a surface of 15.5006 square inches. At this rate the electro-
motive force of the entire mass of air or cloud would be about
17,000,000 kilogrammes, or 37,478,561.25 pounds avoirdupois.
The weight of this large mass of air or cloud is about 500,000,000
kilogrammes, or 1,102,310,625 pounds avoirdupois. Now, the
square root of the ratio of the mass to the force is about 5 ;
hence, the velocity of motion required by the mass in moving
any distance will be five times less than the velocity of a body
falling the same distance under the action of gravity. Under
these circumstances the velocity acquired by the mass in passing

156

over a- mile will be about seventy miles per hour. Two such
masses of air or cloud coming from opposite directions would
thus approach each other at the rate of 140 miles per hour.
But this is the velocity of movement of the two masses in free
space, which condition never actually exists. Under natural
circumstances the electro-motive force of the opposing masses
would not only have to move each mass as a whole, but the en-
tire atmosphere around them. Furthermore, the extreme of
electrical force, under the most favorable circumstances, has
been assumed. Returning to the numerical expressions of force
we find that the work done by 17,000,000 kilogrammes over a
distance, for example, of 2,000 inches is 34,000,000,000 kilo-
grammemetres or 68,000,000,000 kilogrammemetres in both,
which is equivalent to about 200,000,000 foot tons of work. This
quantity of work would cause a cylinder of air 2,640 feet high
and 1,320 feet in diameter to make 400 revolutions per hour.
At the circumference the motion would reach a velocity of about
300 miles per hour, decreasing towards the center. In this rough
calculation the most advantageous circumstances have been as-
sumed, and it is not to be supposed for an instant that these
conditions ever exist in the manner estimated.

65. Assuming variability of heat conditions as the source of
energy in the tornado, we may derive a force which is sometimes
500 times as great as the measure of one atmosphere, while the
force due to electricity can never exceed more than one fifteen-
thousandth of the same pressure.

66. A column of heated air, ascending and drawing in air
from the surrounding regions, would very quickly develop a
rotation possessing an energy which might be tens, and even
hundreds of times, in excess of that due to electricity. Similar
results would follow in case of differently heated masses of air ap-^
proaching each other from opposite directions.

67. If the forces of a tornado are of electrical origin, the tor-
nado once formed must gradually decrease in power and motion
as it advances. But if the theory of heated air is conformable
to truth, the tornado may augment in intensity after formation.
In other words, if the origin is electrical, the maximum power
of the tornado is reached at once ; if calorffic, the maximum

157

power i5 attained gradually and by successive steps. It is not
difficult to, realize that the results of all observation and investi-
gation support the theory of heated air as the source of tornadic
action.

68. All observation and investigation point to the fact that
the development of a tornado is gradual. It is not ushered into
complete existence at the beginning. When the tornado vortex
reaches the earth the extreme violence of the storm is accom-
plished, and this intensity continues undiminished while the
cloud remains upon the surface. It frequently happens that the
tornado vortex is observed to form by the coalescence of several
smaller vortices which play about the central whirl with varying
form and intensity.

69. The larger the volume of air (within vertical limits) em-
braced by the vortex the more destructive the tornado's violence.
Therefore, as the vortex descends from the lofty regions of its
inception, its aggregate energy is constantly increasing until it
reaches the earth.

70. The greater the elevation of the vortex above the earth,
the greater the mass of intervening air to overcome and the
smaller the volume engaged in the production of energy ; con-
sequently, the frequently observed intermissions of energy in the
tornado's path. This intermission does not mean total absence
of force, but only a diminution of the maximum power.

71. Owing to the great centrifugal forces of the tornado-cloud
the center of the vortex must very nearly approach the condition
of a vacuum.

72. The opportunities for the formation of a tornado vortex
in the upper regions of the atmosphere are greater than near the
earth's surface, the density of the air increasing as you descend,
making the resistance to motion in that medium inversely as the
altitude.

73. After the vortex has once formed, it readily descends to the
earth by drawing in the air from beneath it as well as from either
side. Thus the contact of air masses of different temperatures
is secured, rapid condensation follows, and the funnel-shaped
cloud is soon formed.

158

74. As the vortical action of the air becomes intensified, its
power to overcome resistance is multiplied, and tlie descent of
the vortex continues. At the eaith's suiface it overcomes all
resistance, and the dread hour-glass form of the tornado-cloud
soon appears.

75. A tornado is that condition of the atmosphere which
gives rise to the development :*nd maintenance of a vortex,
whose outward visible fashion or fig^ure is a funnel-shaped cloud
that revolves about a vertical axis from right to left.

76. The origin of a tornado is calorific; that is, the phenom-
enon xesults from high-temperature gradients existing in adja-
cent air masses.

77. The concomitants of the tornado are an oppressive or
sultry condition of the air. The gradual setting in and prolonged
opposition of northerly and southerly air-currents over a con-
siderable area. A gradual, but continued, fall of the thermom-
eter, with a prevalence of the northerly currents, and a rise with
the predominance of the southerly. Decided temperature gradi-
ents across the line of progressive movement to the northwest
and southeast. Huge masses of dark and portentous clouds
in the northwest and southwest, possessing a remarkable in-
tensity of color, usually a deep green. — A remarkable rolling
and tumbling of the clouds, scuds darting from all points of the
compass towards a common center. — Hail and rain accompany
the tornado, the former either in unusual size, form, or quantity,
and the latter either in remarkable quantity or size of drops.
The presence of ozone is usually detected in the wake of the
tornado. — A remarkable roaring noise, like the passage of many
railroad trains through a tunnel. The clouds generated by the
vortex assume the form of a funnel with the smallest end towards
the earth. — The vortex has four motions, viz. : ist, the whirHng
or gyratory motion, always from right to left; 2d, the progres-
sive mot'on, generally from some point in the southwest quad-
rant to some point in the northeast quadrant; 3d, the ricochet
motion ; 4th, the oscillatory motion. - The remarkable contrac-
tion of the storm's path. The remarkable definiteness of the
limits of the storm's path. Upon reaching the earth's surface
the vortex assumes the form of an hour-glass.

159

yS. The characteristic effects of a tornado are : Objects are
drawn towards the vortex from every point of the compass.
Objects passing into the vortex are thrown upward and outward
by the vortical action of the engaged air. Structures are Uterally
torn to pieces by the vortical action of the atmosphere, evidence
of which is afforded both by the fineness of the debris and also
its disposition in the storm's path. The debris is thrown inward
from either edge of the storm's path. Light objects are carried
to great heights and also great distances. Objects are carried
inward and upward by the centripetal action of the vortex, and
outward by the centrifugal force. Weight and size are conditions
which present immaterial values to the power of the tornado.
People are stripped of clothing. Fowls and birds denuded of
feathers. Trees are whipped to bare poles. Long and heavy
timbers are driven to considerable depths in the soHd earth.
The vortex is completely filled with flying debris. Timbers are
driven through the sides of buildings. Sand and gravel are
driven into wood. Human beings and animals are run through
with splinters and timbers. Straws, bits of glass, and pieces of
metal are driven into wood. The strongest trees are uprooted
or twisted off near the roots. People and animals are terribly
mangled by the force of the wind and by contact with flying
debris. In the path of the storm all vegetation is destroyed.
Railroad trains are thrown from the track. Iron bridges are
completely dismantled and carried from their foundations.
Heavy boulders, weighing tons, are rolled along the earth. The
largest railroad engines are lifted from the tracks.

79. All objects, whether metal or non-metallic, magnetic or
non-magnetic, simple or compound, animate or inanimate, are
acted upon and with in a similar manner.

80. Every effect is the result of ordinary mechanical motion
with varying degrees of intensity.

81. If it were possible to revolve a mass of air (similar to that
engaged in the tornado's vortex) with enormous velocity by
mechanical means, the characteristic violence of the tornado
would follow.

82. The motive power of the tornado is not and cannot be elec-
trical while our atmosphere remains in in its normal condition.

i6o

83. The peculiar roaring noise which accompanies the prog-
ress of the tornado cannot be ascribed to the intervention of
electrical forces. Within the range of observation and experi-
ment nothing has been brought to light in electrical science
which will authenticate such a statement. It is far more reason-
able to assert that the noise is produced by the resistance which
the rapid and violent indraughts of air encounter while passing
into the tornado's vortex. The vortex approximates a vacuum,
and the air rushes into it at the spout end near the earth with
great violence, attended by a hollow, sucking sound of marked
intensity.

84. All sound is vibration and the sonorous body may some-
times be air. In the tornado it is a vast column of g)Tating air,
within close confines, whose vibrations are propagated through
the surrounding masses of air (not partaking of g}Tatory action)
in every direction.

85. In passing through a body of timber or during the destruc-
tion of buildings the roar of the storm increases because the
sources of sound are augmented ; there is a greater number of
sonorous bodies set in vibration ; the vast and varied mass of
flying debris furnish a multitude of vibrating centers of variable
degrees of intensity, and the commingling and confused succes-
sion of sounds produce an interminable roar.

86. The only possible method for electrical force to effect the
formation of the tornado, would be by some (as yet unknown)
relation of physical agencies to set the air in motion and keep it
in motion (a motion of the most terrific violence) for several
hours. But this result cannot be reached owing to the extremely
low electrical tension of the air. If it were possible, however,
wind would still be the immediate agent of destruction and not
electricity.

87. If electricity enters as the fundamental cause into the
origin of the tornado, it must act likewise throughout the entire
category of atmospheric disturbance. If so, then all wind (air
in motion), however feeble or violent, is of electrical origin. But
this conclusion leads to an impossibility.

88. It is simply absurd to suppose, and much worse to insist,
that electricity directly, by its attractive and repellant forces,
produces the destruction in the wake of the tornado.

i6i

89. If, however, electricity does not act in the manner here
described, its intervention could only be effected by supposing
that the whirling masses of clouds and air were in some inde-
scribable method exerting the power of magnets.

90. A magnet, however powerful, will only manifest its force
in the presence of magnetic bodies or bodies that are capable of
being magnetized.

91. In the tornado, however, all objects receive the violence
of the storm irrespective of magnetic properties.

92. It is claimed that no disruptive discharge of electricity
takes place during the ascensional m.ovement of debris in the
tornado vortex. If so, what produces the so-called electrical
displays in the cloud ?

93. How does lightning appear in the tornado-cloud? Electric
flashes cannot form except by a disruptive discharge. Can it be
explained by saying that part of the electrical force is expended
in flashes and the remainder in moving objects upon the earth ?
Such results would necessitate the existence of an infinite supply
of atmospheric electricity. There is no evidence of any such
quantity in the air or the possibility of producing it through the
intervention of natural agencies.

94. There is no fact or record to show that an electrical dis-
charge or any manifestation of atmospheric electricity ever
entirely demolished a large stone or frame building ; ever car-
ried the debris of buildings for miles in the air ; ever lifted a
locomotive from the track ; ever carried an iron bridge from its
foundations and twisted the frame-work into a shapeless mass ;
ever rolled a boulder from its bed in the ground ; ever imbedded
one piece of timber into another after having carried the former
for several hundred yards in the air ; ever carried bedding and
clothing for miles in the air; ever elevated to considerable
heights in the air columns of water from ponds, lakes, and rivers;
ever lifted animals from the earth and carried them over build-
ings ; ever drew the water from a well or cistern ; ever twisted
a tree from its stump ; ever turned a building bottom side up or
end for end without otherwise injuring it. Many other effects
of the peculiar manifestations of power in the tornado might be
Instanced to illustrate the impossibility of electrical inter v^ention.

1 62

95. There are many effects of electrical force, decidedly char-
acteristic, which are not within the compass of a tornado's
power. This statement may be' reversed with eqaul significance.

96. Lightning is the result of an extremely itensified discharge
of electricity in the open air.

97. The lightning's flash is the result overcoming the electri-
cal tension of the air at any point or succession of points.

98. The concomitants of lightning are : large accumulation
of electric potential, high electrical tension, the presence o
large masses of cumulo-stratus clouds, brilliant flashes and
heavy detonation.

99. The effects of lightning are : rupturing and scaterring of
imperfectly conducting substances and the inflaming of those
which are combustible ; heating, reddening, melting, and
volatilization of metals ; the production of shocks more or less
severe and often fatal to lives of men and animals ; the produc-
tion of ozone, causing a sulphurous odor.

100. The cause of atmospheric electricity is not definitely
known, but its existence has been ascribed to the following
agencies : evaporation, the chemical processes incident to
vegetable life, the friction of solid and liquid particles against
the earth and against each other by the movement of air-
currents.

1 01. By condensation, unelectrified vapor becomes an electri-
fied liquid, and opposite electricities are developed.

102. All atmospheric phenomena involving rapid and heavy
condensation are necessarily accompanied by electrical manifes-
tations.

103. The earth may be negatively or positively electrified, as
also the air and clouds may be possessed of either positive or
negative electrification.

104. Clouds are never insulated from the earth.

105. We may suppose that a mass of comparatively dry air
interposes itself between the earth and a large collection of
clouds for a short time. In such an event, the positive electricity
of the clouds induces negative electricity upon the upper sur-
face of the mass of dry air, repelling the positive electricity to
the lower surface of the mass. The positive charge induces a

163

negative charge upon the earth immediately beneath, and the
two electricities are neutralized, leaving the superincumbent
mass of dry air negatively electrified and consequently repelled
by the earth.

106. The foregoing supposition is theoretically correct, but
such a condition of the atmosphere does not exist.

107. The mass of dry air, if constant and stationary, would
act as a sort of insulator or non-conductor between the clouds
and earth. But the air is constantly in motion, and therefore
the clouds also. The air is constantly changing its degree of
moisture and the tension of its vapor. All of these changes and
others are constantly and decidedly qualifying its degree of
conductivity.

108. Electricity can always be detected in the upper regions
of the atmosphere.

109. In clear weather atmospheric electricity is nearly always
positive. In stormy weather the indications are both positive
and negative, and about as frequently of one sign as the other.

no. Great variations are found to occur in electrical density
in the lower regions of the atmosphere, owing to the rapid and
marked changes in potential in the cloud regions.

111. Assuming the electrical density of the earth as constant,
there are marked differences of potential as we recede from its
surface.

112. Electrical density is greatest on elevated portions of the
earth's surface ; for example, on a mountain peak as compared
with the plain below ; on hills as compared with valleys.

1 13. In all conditions of the atmosphere there is a remarkable
variability of electrical potential. As measured with the varia-
bility of other meteorological phenomena, there is hardly an
element whose fluctuations bear any comparison, either in
extent or rapidity.

114. All observations unite in showing that electrical poten-
tial is greater in winter than in summer ; the most decided min-
imum being in May or June.

115. Diurnal variations indicate the presence of two maxima
of potential, which on the average occur at the hours 9 A. M.
and 9 p. M.

164

1 16. Precipitation from the under surface of a cloud or mass
of clouds may be electrified with a sign opposite to that with
which the upper surface is charged.

117. The combination of the particles of precipitation,
whether of snow, rain, or hail, does not augment the quantity
of electricity or affect the potential, although it may increase the
electrical density of the mass.

118. The electricity of the clouds is constantly fluctuating
through an interminable succession of changes in the electrical
potential of the surrounding air and the neutralizing effect of the
earth.

119. That form of precipitation usually most favorable to the
increase of electrical potential is snow. If accompanied with
high wind the gain is still greater.

120. Electrolysis is the decomposition of certain compound
substances by the passage through them of an electric current.
These substances are therefore called electrolytes.

121. Liquids (they must be conductors) are the only subjects
which are electrolytic.

122. The vapor of water is not electrolytic because it is a gas.
Therefore the assertion that its electrolysis produces the heat of
the tornado is without foundation.

123. Electrolysis is the product of what is termed current
electricity, while the electricity'which is present in the tornado
is called frictional. Therefore no feature of the tornado can
owe its origin to electrolysis.

124. Every electrolyte must be composed of compound mole-
:ules. Even after electrolysis the anion and cation may still be
possessed of a number of molecules of simple bodies. Every
electrolyte in the liquid state becomes a non-conductor when
solidified and thereby loses its electrolytic condition.

125. Pure water has never been electrolyzed because of its
great resistance to electrolytic conduction. The purer the
water the greater its electrical resistance. In fact, pure water
must be acidulated in order to make its conductivity more sus-
ceptible.

i6s

126. All chemical compounds are not electrolytic, and even
compounds containing the same components as electrolytes, but
not in equivalent proportions, are therefore not electrolytes.

127. In an insulated conductor the algebraic sum of the two
electricities which may be induced is equal to zero. But where
the conductor has an independent charge the resulting force of
the induction will be expressed by the algebraic sum of the
force which would exist if there was no independent charge and
the force due to the independent distribution without induction.

128. The forces of attraction and repulsion vary inversely as
the square of the distance from the inductive source. Divide
the distances by 2 multiplies the force by 2. Multiply the dis-
tance by 2 divides the force by 2.

129. The forces of attraction and repulsion depend upon the
amount of the charge. The charge depends upon the size of
the body and the distribution of the electricity.

130. In a good conductor the electric charge passes instantly
from one molecule on another. In fact, the discharge of each
molecule may be considered instantaneous. It is a moderate
conductor or poor insulator. Each molecule may possess for a
very short space of time positive electricity on one side and neg-
ative on the other.

131. In a good insulator the discharge is exceedingly slow,
and therefore a high degree of polarization may be maintained
for a considerable time. The above statements are in accord-
ance with Faraday's theory of induction by contiguous par-
ticles."

132. The peculiar sensations of what are termed burning,"
"scorching," or "stifling heat," which are reported by those
who experience the violence of the tornado's vortex, must
be due to the latent heat of vaporization which is given off
in great quantities by the extremely rapid condensation that at-
tends the tornado as a constant feature. A numerical expres-
sion may be given to the above by stating that a pound of vapor
of water at the temperature of 100 degrees centigrade will pro-
duce 536 degrees of sensible heat, upon being condensed at the
same temperature.

i66

133. The amount of lament heat hberated in the process of
condensation depends upoji the temperature at which the modi-
fication is effected. The lower the temperature (other things
being equal) of the vapor the less the quantity of heat made
sensible by condensation.

134. In the tornado the temperature of the vapor of water is
considerably lower than given in the previous example, conse-
quently the sensible heat is less when condensation takes place.
But the enormous mass of vapor condensed in part overcomes
this deficiency, and the total quantity of sensible heat which
may be experienced will be quite sufficient to produce uncom-
fortable sensations.

135. With the sensation of heat there appears to be experi-
enced a peculiar difficulty for breath. This effect is probably
due to the extreme rarit)' of the air in the vortex consequent
upon the violent centrifugal action of the currents.

136. The peculiar sensations of cold experienced in the path
of the tornado may be due to marked differences of temperature
between the interior of the tornado-cloud and the air surround-
ing it. The sensations as reported by observers appear to be
relative rather than absolute. Observers always first experience
a stifling heat and then a chilling cold. The latter condition
never precedes the former. The cold is always encountered
just after the period of maximum violence of the storm. A cold
current sets in from the west and northwest in the wake of the
tornado. The temperature of this current under ordinar}^ cir-
cumstances would not produce a chilling effect, but because of
the abnormal conditions in the tornado, the obsen^er's first ex-
perience places him in decided contrast with that which imme-
diately follows. The change is similar to %vhat would be
experienced in passing from the moist, hot air of a bath-room
into the cold, dry air of an ice-house. In either case the ex-
tremes of temperature may not be marked, but the sudden
change from one to the other produces a painful shock to the
system.

137. Electrical forces always act in straight lines, while the
forces of the tornado may be exerted in either straight lines or
in those directions embracing the most complicated cur\^es.

167

Can any manifestations of electrical force twist the body of a
hickory tree several times about the same vertical or horizontal
axis ?

138. We have said that electrical manifestations accompany
or attend the tornado, but do not cause the storm. This
kind of electricity is called statical or frictional as opposed to
voltaic or current electricity. The latter is believed to be the
only form of electricity which will produce electrolysis. Experi-
ments have been made with the electric spark in an attempt to
produce electrolysis, but the efforts were not successful. The
electric spark (statical electricity) will, under certain circum-
stances, produce what may be called a dissociation of certain
compound substances, but this phenomenon can not be consid-
ered electrolysis.

139. Faraday estimates that the quantity of statical electricity
required to decompose one grain of water is 800,000 times as
much as would be required to kill a cat. Expressing this force in
other terms, we find that the quantity of static electricity required
to decompose a grain of water would, if it charged a cloud situ-
ated at a distance of 3,281 feet above the earth, exert an attractive
force between the cloud and the earth beneath it of 1,497 tons.
Suppose the area of the above cloud to be 50 by 38 feet, the
attractive force is otherwise expressed as one ton per square foot
of surface. This illustration of comparative electrical forces is
not intended for one moment to argue that these conditions ever
really exist in the atmosphere. The purpose is to show the
comparative electrolytic properties of statical and voltaic electrici-
ties, and to make evident the absurdity of reasoning that the
high temperature of the tornado vortex is due to the electrolysis
of atmospheric vapor.

140. In explaining the electrical origin of the tornado and
asserting that the electricity present acts as usual between two
opposite polarities, the inference does not follow as maintained,
viz.: That one pole being given it induces the opposite pole on
the nearest point of matter adjacent to it. This assumes that
the highest objects on the surface of the earth are subject to the
greatest electrical influence simply because they are the highest.
Now, it is admitted that elevation is a decided advantage in the

i6t

comparative influence of the electrical forces of attraction, but
without another accompaniment elevation has no superiority.
The object, high or low, must be electrically connected with the
earth. The lightest or the most lofty of objects could not be
moved from their foundations by the most powerful electric
charge if they were insulated from the earth. The principle
here involved is illustrated by that old electrical experiment of
Volta's, by which pith balls were made to fly back and forth be-
tween two metallic plates oppositely electrified. The moment
the lower plate is insulated from the earth the balls are repelled
from the upper plate and remain stationary upon the lower one,
showing that the force of attraction is lost the instant that elec-
trical connection with the earth is broken.

141. Any method of reasoning which assigns tornado develop-
ment to planetary influences is, equally with the electrical theory
of their origin, without foundation. We have but to realize that
in the formation of the tornado and other local storms of a sim-
ilar character the entire action of all the forces involved, except
the energy of the sun's heat, is embraced in that portion of the
atmosphere within from two to three miles of the earth's sur-
face. Any influence emanating from the movements, conjunc-
tions, or other periodical mutations of the heavenly bodies, dis-
tant hundreds of thousands and millions of miles, can only reach
an infinitesimal amount, and entirely inappreciable in its effect
upon the atmosphere to produce local or general disturbances,
especially near the earth.

142. It has been asserted that the conditions which give rise
to the formation of the tornado- cloud result from the effect upon
the atmosphere of the mere revolution of the planets in their
orbits. That circular movements in the atmosphere are propa-
gated and continued by such influences. The effect is likened
to that which would result from the whirling in different direc-
tions in a large vessel of water of several globes attached to the
same spindle. Upon withdrawing the globes after a number of
revolutions, the surface of the water would be found covered with
a network of eddies. The inherent fault of this simile is the fact
that while the illustration provides for the circular movement of
the bodies within the medium which is set in motion to give the

169

characteristic whirls or eddies, the subject of illustration, the
planets, perform their revolutions, not in the atmosphere, the
medium to be set in motion, but millions of miles away from it
in another medium, concerning which little is known. The
failure to properly apply the method of reasoning by analogy
often leads the novice into making the most ridiculous assump-
tions. It would be more reasonable to assume that the revolu-
tions of the planets give rise to the great disturbances of the
atmosphere, embracing extended regions of country, which are
known on the weather-map as ''Highs" and '* Lows," but even
here the same difficulties operate, although not so extravagant
as in the case of the tornado with its narrow path of a hundred
yards or more.

143. Finally, the tornado is the result of an accidental condi-
tion of the atmosphere ; and, therefore, it cannot be due, as
many believe, to some periodical influence emanating from the
movement or relative position of the planets, which conditions,
of course, recur with the most exact regularity. When the ten-
sion between the opposing currents of warm and cold air sud-
denly and unexpectedly becomes broken at any point, centripetal
action sets in and the funnel-shaped cloud soon appears, not
through some mysterious and improbable agency, but by a rea-
sonable and natural operation of well-known physical forces.

INSTRUCTIONS FOR OBSERVING WIND-STORMS.

The following is a full and complete copy of the Tornado Cir-
cular No. I, New Series," issued from the Signal Office at Wash-
ington for the guidance of persons who desire to aid in observing
wind-storms. The entire circular is inserted here as a thing of
great value. The questions are classified under headings, which
briefly refer to the general character of the data desired; the de-
tails being covered by the questions themselves. Persons mak-
ing observations for the purpose of forwarding them to Wash-
ington should number their communications according to the
following arrangement: For example, " Wind Direction No, 6
— Northwest, 5:30 A. M." Observations with as full particulars
as can be collated should be promptly forwarded to the Chief
Signal Officer of the Army, Washington, D. C,

SUBJECTS AND QUESTIONS

DATE, TIME, AND CHARACTER OF STORM.

1. Give the year, month, day of month, and hour of day
(hour and minutes, and A. M. or P. M.) when the storm oc-
curred.

2. Did you have a storm on the above date ; and, if so, what
was the nature of it, and from what point of the compass did it
approach ?

3. When time of day is asked, give the same in hours and
minutes, and state whether it is local or railroad time, and by
what standard, viz.: Chicago, Detroit, Columbus, St. Louis, etc.,
etc.

4. What time of day did threatening appearances commence,
in what portion of the horizon, and at what time were they the
most decided ?

5. The time of day when the tornado-cloud passed.

WIND DIRECTION.

1. The direction of the wind while the tornado-cloud was ap-
proaching.

2. The direction of the wind while the tornado-cloud was
passing.

3. The direction of the wind after the tornado-cloud passed.

4. The direction of the wind during the forenoon of the day
and up to the time of the first threatening appearance in the
heavens.

5. The prevailing direction of the wind at this season of the
year.

6. What was the direction and force of the wind when you
first noticed the weather in the early morning ? Give the hour
of observation.

7. When direction of wind is asked, the direction of motion of
the air-currents is meant, independent of the course or motion
of the tornado-cloud. Always give the points of compass from
which the wind comes.

TEMPERATURE OBSERVATIONS.
I. Was the day unusually warm and sultry ? Give the maxi-
mum temperature, if possible, and state the hour at which it

171

was observed, together with the direction of the wind and the
state of the sky existing at the time.

2. What was the condition of the temperature after the torna-
do-cloud passed? Did the air suddenly, or gradually, grow
colder ? Give the minimum temperature for that afternoon and
evening, and during the night, with direction of the wind.

3. What had been about the average daily temperature, also
the maximum and minimum, together with the accompanying
direction of the wind, humidity, and clouds, for two or three
days previous to the occurrence of the tornado and for three
days succeeding its appearance ?

MOTION OF TORNADO-CLOUD.

1. Describe the character and motion of the surrounding
clouds before, during, and after the tornado-cloud passed.

2. Give the time of day at which the light or dark irregular
clouds surrounding the tornado-cloud were in the greatest con-
fusion, and describe the scene.

3. If you saw the tornado-cloud, describe or sketch it, and
note particularly any change in motion or the successive stages
of development during the time of observation.

4. Give the direction of the whirl of the tornado-cloud, as
against, or with, the hands of a watch, face upward.

5. Give all the motions of the tornado-cloud which you ob-
served, or which you heard that others had witnessed, as, for
example : rising and falling, swaying from side to side, or whirl-
ing about a central axis, etc., etc.

6. Describe minutely the manner in which objects were car-
ried inward, upward, and about in the whirling vortex of the
tornado-cloud ; how thrown outward, and from what portion of
the cloud.

7. Give the direction of the course pursued by tfie tornado-
cloud along its path of destruction in your locality, as, for exam-
ple : N. 70° E.; E. 30° N., or E. 20° S., etc., etc.

8. Did the tornado-cloud remain in a vertical position as it
traveled forward, or was the' tail of it inclined ; in what direction,
and how many degrees from the perpendicular ?

172

g. Give an estimate of what you consider the progressive ve-
locity of the tornado-cloud; how many miles per hour. Give
the data upon which you make the estimate, and why you be-
lieve your estimate to be reliable.

10. As the tornado-cloud approached, from what direction
came the wind you first experienced, whether against your
body or against the building within which you were situated at
the time.

11. Try and give an estimate of what you consider the wind's
velocity within the central whirl of the tornado-cloud, and also
the data upon which you base this estimate.

12. In the passage of the tornado-cloud over a pond, lake, or
river, carefully describe every particular in the disturbance of the
water; how high into the air any portion of it was carried; if
any fish, shells, stones, or the like, were carried out, and in
what direction. Also state the exact position of the person, or
persons, who witnessed the scene.

13. Were bits of leaves, mud, straw, grass, or the like, thrown
against your building ? If so, state on what particular portion
or portions, and whether apparently thrown thereon with great
force. If thrown upon the bodies of persons or animals, care-
fully state the circumstances.

FORM OF TORNADO-CLOUD.

1. How many funnel-shaped clouds did you see? Describe
each, giving their relative sizes, shapes, and positions, and, if
possible, a rough sketch of each.

2. Describe the color of the tornado-cloud ; its density ; how
and when changes in color and density occur ; the color and
density of the bottom of the cloud as compared with the top ; the
existence of light and peculiar fleecy clouds over and about the
upper portion.

3. Give the comparative size of top and bottom of tornado-
cloud; note particularly and describe minutely any change in
form when the bottom or tail reached the surface of the ground.

4. In observations upon the tornado-cloud, please note the
angular height of the top of the cloud from the horizon, that is,
above the plane of the horizon ; also the horizontal distance from

173

the observer to the bottom of the tornado-cloud. Carefully esti-
mate the angular height in degrees, and the horizontal distance
in yards or miles.

HAIL OBSERVATIONS.

1. If a hailstorm, state whether the hailstones were large or
small, of peculiar shape, and few or many in number. Give ex-
act size and weight of some of the largest.

2. Did you examine the interior of any of the hailstones, and
if so, how were they formed, and what did they contain ?

3. If hail fell at intervals during the day, state the times
of beginning and ending of each precipitation separately, to-
gether with the direction of the wind at each occurrence.

4. Was there any peculiar condition of the clouds at the time
of the hail ? If any strange feature was noticed, give details.

5. On which side of the tornado's path (to the N. or to the
S. ) did the hailstones appear to fall in the greatest quantity ?

6. Did the hail fall before or after (how long) the tornado-
cloud passed ?

7. Did you notice any distinct peculiarity in the approaching
or overhanging clouds from which the hail itself fell ? Did the
hailstones appear to drop from the funnel-shaped cloud, or from
the surrounding clouds?

RAIN OBSERVATIONS.

1. Any rain, and did it fall before or after (how long) the tor-
nado-cloud passed ?

2. If any rain fell during the hailstorm, be careful to state
whether it fell before, at the tune of, or after the hail ceased. In
case of the two extremes, give the interval in minutes.

3. On which side of the tornado's path (to the N. or to the
S. ) was the rainfall the heaviest .'^

4. If rain fell at intervals during the day, state the times of
beginning and ending of each precipitation separately, together
with the direction of the wind at each occurrence.

5. Any peculiarity in the size of the rain-drops, or in the
quantity which fell ?

174

ELECTRICAL OBSERVATIONS.

1. Was thunder or lightning observed, and if so, in what por-
tion of the horizon, at what time of the day, and whether violent
or otherwise ?

2. Was lightning or other manifestation of electricity seen in
the funnel-shaped tornado-cioud as it approached or passed, or
in the dark, heavy clouds surrounding it to the N. and W.?
If so, describe the appearance minutely.

3. Do you know of any one who made observations concern-
ing the deflection of a magnetic needle during the day of the
storm, especially while the tornado-cloud was passing a given
point? If so, send his address, or give the result of the ob-
servations.

4. The terms lightning and electric discharge, as used in
this circular, are synonymous.

5. How can one determine whether electricity has ^/tk influence
in aiding the development and progress of the tornado, or is only
an uni^nportant factor ?

6. Is there any reason to suppose that the clouds approach-
ing from opposite directions, preceding the first appearance of
the funnel-shaped cloud, were oppositely electrified ?

7. Did lightning tend to pass between the approaching clouds ?

8. Did the motion of the approaching clouds appear to be
accelerated at the moment of, or immediately following, any
electric discharge ?

9. Were electric discharges observed to take place in the in-
itiatory whirl of the approaching clouds ?

10. Were electric discharges observed to take place between
the cloud-spout and the earth, while the former was yet at a
considerable elevation in the air ?

11. Is there any competent evidence to show an increase of
electrical manifestation upon the descent of the cloud-spout to
the earth ?

12. Was lightning observed in the heavy bank of clouds
along the western horizon after the tornado-cloud had advanced
beyond this cloud region to the eastward 1

13. Are electric discharges which take place in the bank of
clouds along the western horizon visible to an observer situated

175

to the eastward and in advance of the approaching tornado-
cloud ?

14. Can flashes of Hghtning which issue from the clouds
along any portion of the western horizon be seen through any
portion of the tornado-cloud ? What portion ? May not the
flashes appear as if passing through the tornado-cloud from top
to bottom, when really they are among distant clouds ? It is
important to determine whether the flashes of lightning, some-
times reported as appearing in the tornado-cloud, are not the
result of an optical illusion.

15 What portion of the tornado-cloud presents the lightest
color ?

16. Cannot flashes of lightning be readily seen to descend to
the earth at the right, left, and rear of the tornado-cloud, but
evidently not emanating from it ?

17. Does the upper portion of the tornado-cloud at any time
present a glowing appearance, like the colors of a brilliant sun-
set?

18. Does any portion of the tornado-cloud ever present the
appearance of sunlight passing through fine mist or rain-drops ?

19. Always note the absence or appearance of the sun
(whether obscured by clouds or not) while making observations
upon the tornado-cloud. Give the position of the tornado-cloud
with respect to the sun.

20. Note the condition of the sky between the tornado- cloud
and the horizon at the right, left, and rear — clear, fair, or
cloudy? Describe carefully.

21. Were balls of fire " observed to accompany the tornado-
cloud at any stage of its progressive movement ? Did they ap-
pear to come from the tornado-cloud, or surrounding clouds ?
If from the former, from what portion of it, under what condi-
tions, and with what result ? Reply to this entire question very
carefully.

22. What effect had the tornado upon small vegetation and
the foliage of trees? How long after the tornado passed before
there was observed any brown or seared appearance of leaves
and stems, or any chan ge of color on the trunks or limbs of
trees or shrubs where the bark was broken or peeled off?

176

23. In the event of death or injury to any person or animal,
observe very carefully whether the effect resulted from electrical
discharge or the force of the wind.

24. In the destruction or removal of an> object within the
path of the tornado, observe very carefully whether the effect
resulted from electrical discharge or simply the force of the
wind.

25. During the progress of the tornado does the air appear to
rush into the cloud vortex from all points of the compass, or
does it advance from only two points, viz., northwest and south-
west? This information can probably be secured either by
witnessing the passage of the tornado-cloud or carefully examin-
ing the disposition of the debris after the storm has cleared
away. Light winds occurring on one or more sides of the center
should be recorded as well as the destructive winds.

26. Observe whether the debris in the tornado's path appears
to have been thrown down and carried about by the action of a
continuous wind, or was the distribution the result of separate
winds, operating successively in a direction veering around
from right to left.

27. In the incipient stages of the cloud-spout does the air ap-
pear to rush in from all sides towards the point of inception, or
does the air come principally from the northwest 2ltA southwest?
This information can probably be secured by observing the
formation of clouds and their directions of movement, carefully
distinguishing between the several strata.

28. If possible, carefully determine whether the energy of the
tornado increases or gradually diminishes after it has been per-
fectly formed. To ascertain the facts in this case it will proba-
bly be necessary to make an examination embracing the entire
path of the tornado, or the larger portion of it.

29. Can the roaring, which always accompanies the tornado-
cloud in its passage over the country, be readily distinguished
from ordinary thunder ? Is thunder ever distinctly heard as
emanating directly from the tornado-cloud ?

30. Carefully examine buildings, trees, and other objects
which have been acted upon with marked severity by the tor-
nado, and ascertain if there is good evidence of electrical action.

177

3 1 . Try and secure some observations upon the variability of
atmospheric electricity in the immediate vicinity of the tornado's
path. What effect was observed in telegraph offices? How
were the telegraph lines affected? To what extent was the
magnetic needle affected ?

32. The effects of lightning are : rupturing and scattering of
imperfectly conducting substances and the inflaming of those
which are combustible ; heating, reddening, melting, and vola-
tilizing of metals ; the production of shocks more or less severe
and often fatal to the lives of men and animals, and the produc-
tion of ozone, causing a sulphurous odor.

In conducting an examination over any portion of the tor-
nado's path, carefully determine whether any of the above ef-
fects are present.

33. Report all damaging effects by lightning, whether con-
nected with a tornado or attendant upon some general storm.
Describe the conditions of each case prior to the damage and
then follow these facts by carefully statmg all the particulars of
injury. Make a personal examination of each case when prac-
ticable. State whether the object damaged was protected from
injury by lightning in any manner and how. Note the disposi-
tion of debris about the object damaged, or surrounding its lo-
cation^ if entirely destroyed.

34. Of a building or tree, note its height above the ground
and its position respecting other objects.

35. Of persons or animals, describe their location at the time
of damage with respect to other objects, and in case of persons,
the character and condition of their clothing.

36. Give the hour of day when damage occurred. Send
newspaper items regarding the damage.

METEOROLOGICAL OBSERVATIONS.

1. If no tornado occurred at or near your station, please state
whether you experienced any sort of a storm, and give the nat-
ure of it.

2. Did you hear a roaring noise on the approach of the storm,
and if so, state in what direction, the intensity, or any accompa-
nying peculiarity ?

178

3. Did you notice any peculiar odor in the atmosphere during
the passage of the tornado-cloud, and what was it like ?

4. Do you know any one who made observations on the pres-
ence of ozone in the atmosphere on the day of the storm? If so,
send his address or give the result of his observations.

5. What was the condition of the sky when you made your
first observation in the morning ? Was it cloudy, three-fourths
cloudy, one-half cloudy, one-fourth cloudy, or entirely clear?

6. What was the direction, or directions, in which the clouds
were moving at the time of your first observation ?

7. What time of day did it commence to cloud up, and in
what quarter of the heavens ?

8. Describe the character of the clouds when the first threat-
ening appearances began.

9. Give the time of day, the quarter of the heavens, and the
character of each formation, if there were frequent and sudden
changes in the development or grouping of the clouds.

10. How many days previous did you notice any indications of
an approaching storm, and what were those indications ?

11. Did you observe the form of cloud commonly called
mare's tails " (cirrus) ; in what part of the heavens and how

many days previous ?

12. In what quarter of the heavens did the passing storm seem
to be the heaviest ?

13. What time of the day did the first threatening appearances
commence, and in what portion of the heavens ?

14. How did the day open?

15. Did the clouds gradually thicken on this day, or was
there a sudden and portentous banking up of them in the W.
during the afternoon ?

16. Did the clouds appear to gather near the earth and extend
in irregular forms to great heights, or was there a heavy, dark
mass, with comparatively regular outlines, hanging low down in
the W. ?

17. What time during the day, and in what portion of the
heavens, did you notice small light or dark clouds, if any, driven
swiftly by the wind? Tell how they moved, from what direction
or directions they came, and where they seemed to concentrate.

179

1 8. In describing clouds, especially where they are peculiar or
portentous in appearance, aside from indicating character or for-
mation, give the most striking colors and state how they blended
with each other.

19. In the event of the occurrence of any storm, state whether
it passed your location by either the N. or S. point, or directly
overhead.

20. What time of the day did you notice any decided change
in the temperature, and what was the extent of that change ?

21. In making a statement concerning any feature of- the
weather during the day, be careful to give the hour at which the
condition referred to was observed.

METEOROLOGICAL INSTRUMENTS.

I. If you, or any of your neighbors, have meteorological in-
struments, give the readings of the thermometer and barometer,
direction of the wind, and the hour of observation, for two days
before, on the day of the storm, and for two days thereafter.

DRAWINGS, SKETCHES, AND PHOTOGRAPHS.

1. If possible, try to represent the tornado-cloud by a rough
sketch, as also the dark and irregular clouds surrounding it.

2. Give the direction and distance from your house to your
various farm buildings, if possible drawing a plan of the same
and indicating the points of the compass. This plan need only
be a rough sketch.

3. Give the dimensions of your buildings, and state the char-
acter of each as to whether they are log, frame, stone, or brick,
and weak or strong.

4. In drawing a plan of your buildings, indicate the position
of the tornado's path with respect to each of them and the direc-
tion in which the tornado-cloud moved.

5. If possible, please furnish photographs, sketches, or printed
cuts representing the tornado-cloud or some evidence of its de-
structive power. They are very desirable. If you cannot furnish
them, perhaps you know of some one who can. This office is
desirous of obtaining sketches of clouds, however rough and im-
perfect. If in any way you can readily depict upon paper the un •
roofing, overturning, or crushing of a building, the destruction

i8o

of an orchard, uprooted or tsvisted trees, or the falhng or twisting
of timber as the tornado-cloud swept through the forest, it will
be valuable. Perhaps you know of some one who witnessed these
scenes, or part of them, and who would be willing to illustrate
them.

6. Sketches of clouds of peculiar destructive effects, of hail-
stones, of anything that will illustrate any distinguishing feature
of the storm's violence, are very desirable.

GENERAL DESTRUCTION TO PROPERTY.

1. How far, and in what direction, are you situated from the
center of the path of destruction ?

2. Give the maximum and minimum width, in yards or rods,
of the path of destruction in your vicinity, and state, if you can,
whether in examining that path it was found that on the S. side
of the center the sweep of destruction was broader and more ir-
regular than on the X. side, or if any other difference existed
between the two sides.

3. In giving your distance from the center of the path of de-
struction, indicate the same in miles and parts of miles or rods,
stating the amount in northing and easting, northing and west-
ing, southing and easting, or southing and westing, estimated
along section or township lines.

4. In all descriptions of the tornado's path, In gi\'ing any par-
ticular destruction in it, or in detailing your experience while the
tornado-cloud was passing, be careful to state on which side of
the center (to the N. or to the S., and how far) the damage oc-
curred, or you were situated while a witness of the storm.

5. In the destruction of any building, whether unroofed, over-
turned, moved from the foundation, racked, or othen^ise dam-
aged, be very careful to state how the destructive force operated.
Did the wind or tornado-cloud, or whatever you may term the force,
cause the damage \i\ piilli?ig^ drdu'ing, or ^//ri'//^^ the building,
or any portion of it, inward to the center or outward from the cen-
ter of the storm's path ? Apply this same question to the puUmg
of fence-posts, uprooting trees, moving of machiner}-, or other
heavy- objects or animals. Did the destructive force operate as
an ordinary- wind in any sense, whether such wind be gentle or

i8i

violent ; or, rather, was this force some mysterious, irresistible
power, impelUng an object (no matter how large or weighty) to
move, as if the pressure of the atmosphere in front of it, or round
about it, suddenly gave way, without your knowing how? Did
buildings suddenly seem to totter ; trees in an instant bend to
the ground; the pressure of the air against your body give
way all at once, or small objects move swiftly into the air or
over the ground, and yet all this happen without apparently any
wijtd? Take great care in giving facts concerning this point.

6. Give an estimate of the number and kind of buildings de-
stroyed.

7. Give a similar estimate of the total valuation of property
of all kinds destroyed.

8. Give the length and width of the tornado's path which
passed through your section of the State.

9. Give the position of your house with respect to the nearest
post-office, indicating the same in miles and parts of miles or
rods ; state the distance in northing and easting, northing and
westing, southing and easting, and southing and westing, esti-
mated along section and township lines.

10. State in detail and separately the damage to each build-
ing; what portion or portions were taken away or injured ; how
5ar and in what direction they were moved bodily ; what portion
of each was first struck by the wind, and how far and in what direc-
tion the debris was carried. Be very careful to give the exact
position and peculiarities of structure of the buildings which were
not damaged, although standing near those which were destroyed.

11. In the damage or destruction of each or any building,
state particularly how far and in what direction any portion of
them was carried a considerable distance.

12. If any object was carried a long distance by the force of the
wind, state where and what it came from ; its dimensions ; its
shape ; probable height to which transported in the air ; whether
driven into the ground or not, how far and into what kind of
earth.

13. State whether articles of clothing, fowls, or animals were
carried into the air, to what height, to what horizontal distance,
and in what direction.

l82

14. Give detailed destruction of furniture contained in the
house and of farming implements in and about the barns.

15. Be particular to note any evidence of the wind's extreme
violence, as in the lifting of heavy objects ; the twisting of trees
or heavy pieces of timber f puUing up of fence-posts ; removing
heavy stones, etc., etc.

16. With regard to destruction in orchards, among shade-
trees, and in forests, be particular to give the direction in which
the trees lie ; how they lie on the two sides with regard to each
other and to the center of the path of destruction ; any special
acts of violence in the twisting, uprooting, or breaking off of
heavy timber ; give circumference of large trees, height above
ground where broken off, and dimensions of earth and roots
where notably large trees were overthrown.

17. In general, when giving the position of any person or thmg
with regard to the center of the path of destruction, state the
distance in feet or rods, and the direction, as N. or S.

18. Give the maximum and minimum width, in yards or rods,
of the path of destruction in your locality.

19. Did you notice any peculiarity with the manner in which
small objects were suddenly removed from around about build-
ings, as if sucked in by the advancing cloud ?

20. Did you notice any peculiarity in the falling of trees as tne
tornado-cloud advanced upon them ? Were they whipped about
and bent to and fro as in a heavy wind, or were they drawn
steadily inward toward the center on both sides, as if by some
mysterious but irresistible force ?

21. How many rods of fencing (stating kind) did you have
blown down; in what direction were the N. and S. fences car-
ried ; what was the direction in which the E. and W. fences were
carried ?

22. Give an estimate m money value of the loss to your prop-
erty occasioned by the tornado, the number of acres of timber
you had destroyed, and the number of fruit-trees you had up-
rooted or broken off.

23. Be particular to give the exact position, also the dimen-
sions and probable strength and weight, of small objects which

i83

were not moved from about large buildings, although the latter
were entirely destroyed.

24. In examining the path of destruction, did you find any
difference between the N. and S. sides of it ? Which side was the
widest ; which the cleanest cut ; which the most irregular and
jagged along its outer edge ; on which side were narrow paths of
destruction cut inward toward the center ?

25. In describing the path of destruction, be careful to note
where the tornado-cloud left the ground, where it again de-
scended, the length of the interval, and the topography of the
earth at the points of ascension and descension. Also state
whether the hail and rain continued to fall after the tornado-
cloud rose from the earth and disappeared in the overhanging
clouds.

26. Estimate the time in minutes or seconds during which the
tornado-cloud was committing the destruction at your buildings
or in passing them at a safe distance.

27. In the destruction of your buildings, did you notice any-
thing in the disposition of the debris after the tornado-cloud
passed that would indicate the effect of an explosion, as, for ex-
ample, the sides and the ends of a building being thrown out-
ward and the roof carried off or let down upon the floor ?

28. Where trees were overturned and wrenched or twisted by
the force of the wind, describe minutely how and in what direc-
tion the twist runs — that is, its direction, as with or against the
hands of a watch. Perhaps you can compare it with the bit of
an augur or indicate the same by a rough pencil sketch. Also
state what portion or portions of the tree were twisted, and what
the kind of timber in the case of each tree so affected.

29. Observe carefully where the tornado-cloud passed through
forests, and state on which side of the tornado's path (to the N.
or S.) the trees were broken off at a considerable height
above the ground; the maximum and minimum height; gener-
al size of trees so affected; kind of timber, and whether broken
square off or twisted. Try and illustrate the path through the
timber by a pencil sketch showing the various directions of the
prostrated trees. Indicate the points of compass.

i84

INJURY TO PEOPLE AND ANIMALS.

1. State the number, kind, and in what manner, stock were
killed or injured, and whether at the time of the storm they were
in or without buildings. Also narrate any miraculous escapes of
hfe.

2. With respect to your family, give the whereabouts and con-
dition of each person on the approach of the tornado, and also
after the tornado-cloud passed. Give age and sex of each per-
son, and particularize the character and extent of injuries to each.
State very carefully the distance and direction in which any of
the persons were carried, and also narrate any miraculous es-
capes of life.

3. In describing the injury to any person, animal, or object,
never fail to give the distance and direction of such person, ani-
mal, or object from the center of the path of destruction at the
time the tornado-cloud passed.

4. Estimate the number of persons killed and wounded along
the entire path of the storm.

5. Give a similar estimate of the number and kind of animals
killed or injured.

WIND FORCE AND VELOCITY.

I. To indicate the force of the wind, use the following scale,
expressing the velocity in miles per hour, if you have an ane-
mometer; or if not, estimate the same by employing the appro-

priate terms here given.

0 Calm.

1 to 2 miles per hour Light wind.

3 to 5 miles per hour Geutle wind.

6 to 14 mUes per hour Fresh wind.

15 to 24 miles per hour Brisk wind.

25 to 39 miles per hour High wind.

40 to 59 miles per hour Gale.

60 to 79 miles per hour Storm.

80 miles per hour and above Huiricane.

2. Where it occurs that a heavy body has been transported by
the force of the wind, please give weight, dimensions, and form ;
also distance carried.

3. What was tiie highest velocity of the wind in miles per
hour, and the direction from which it came ? Approximate the
velocity \i you can do no better.

i85

4. What was the time of day when the maximum velocity oc-
curred.

5. Can you give the temperature at the time the highest wind
velocity occurred ? If not, say whether it was warm or cold.

6. In the event of any storm whatever, give the direction and
force of the wind while the storm was approaching, while the
storm was passing, and after the storm passed. If a number of
storms occurred on this day, give particulars of each.

7. At what tune, or times, of the day did you notice any fresh-
ening of the wind, and what was the direction at each occur-
rence ?

8. It is both a matter of great interest and much value to de-
termine high-wind velocities such as are common to the violence
of the tornado. The important question involved is the relation
of velocity to pressure. This relation varies among other things
with the altitude above the earth's surface, the form and size of
surface of impact, and the elements of friction. Experiments
have been made with square and spherical surfaces of very small
dimensions, giving certain results, which for purposes of applica-
tion have been expressed in the language of simple formulas.
For surfaces of large extent application of these formulas will give
approximate results, but the error for ordinary purposes may be
ignored.

For square surfaces at the earth's surface : —
P = (0.0027 A V^).

P = pressure of the air in pounds per square foot.

0.0027 is the constant determined, theoretically.
A = the area in square feet of the surface against which the
wind blows.

V = the velocity of the wind in miles per hour.
For square surfaces at any altitude : —

P= 0.0027 A V^^^^/_^L/,

The terms of this expression have the meaning as given in the

first formula, except the fraction which is explained as

follows : —

P = the pressure at the upper station.

i86

P(, = the pressure (standard) at sea-level or lower station.

I + L / = I -h 0.003665 t, / being the temperature of the air
at the .time of observation, and 0.003665 being the co-efficient of
the expansion of air for one degree at a constant temperature
and pressure.

All measurements of surfaces should be made with the utmost
care. Wherever the object acted upon is not placed at right
angles to the direction of the wind, the exception should be noted
and the angle measured and reported. In cases where stone
shafts *are broken off by the force of the wind, all of the circum-
stances should be carefully described. Note particularly if the
broken surfaces are chipped, and if so, to what extent.

The following table furnishes the means of comparmg pounds
pressure per square foot with velocity in miles per hour in ac-
cordance with the terms of the formula previously given.
P = .003 A V^; assume A = i sq. ft.

Miles per Hour.

Units.

Tens

Miles

100

102

103

105

106

108

109

111

113

114

117

118

120

121

123

124

125

126

128

129

PAST TORNADOES OR "WINDFALLS."

1. If you recall the occurrence, in times past, of any violent
hailstorm in your State, give the place, year, month, day of
month, hour of day, direction of the storm, maximum and min-
imum width of path in rods or miles, size and shape of hailstones,
and a narration of the destructive effects.

2. If you recall the occurrence, in times past, of any other
tornado in your State, give year, month, day of month, hour of
day, the direction of the course of the path of destruction as pur-
sued by the tornado-cloud, its length in miles, average width of
destructive path in yards or rods, maximum width, minimum

i87

width, and, if possible, the hour of beginning and hour of disap-
pearing of the tornado-cloud.

3. The following questions relate to old land marks
through the forests, well known by the name of windfalls."
In early times violent local storms of wind, rain, and hail
swept over portions of newly settled country, marking their path-
way by fallen timber, which in the heavy forests was cut down
in swathes or lanes, narrow but well defined. You are invited to
furnish such information as you can conveniently concerning
this subject. It is not presumed that any one person will be able
to answer every question propounded. Dates are especially im-
portant, but it is realized that to authenticate their accuracy will,
in many cases, be difficult. Always furnish dates when any are
reported, even though doubtful, and note the doubt. Perhaps
you can associate the occurrence of the storm with some prom-
inent event in the history of county or State, and thereby re-
move obscurity concerning the date. Some of the questions
call for data which anticipate the examination of records : —

QUESTIONS.

4. Date of storm : year, month, day of month, and time of
day.

5. Location ot storm's path: give distance in miles and frac-
tions of a mile to the nearest post-office or county court-house.

6. Direction of storm's path : by points of compass, expressed
in degrees, if possible.

7. Width of storm's path : average width in rods or yards.

8. Length of storm's path in miles and fractions of a mile.

9. Character of timber through which the storm passed, and
the approximate amount of destruction.

10. Describe the disposition of the debris in the path of the
storm. How was it disposed witl^ reference to the north and
south sides of the path ?

11. Was the storm accompanied by an unusual roaring noise ?
Describe it.

12. Any hail or rain ? Describe the character of the precipi-
tation.

13. Describe the form of the storm-cloud and its peculiar mo-
tions, especially any motion about its axis.

i88

14. Was there any display of electricity accompanying the
storm ? Describe fully, and note any destruction by this force.

15. Was the day of the storm unusual with respect to temper-
ature, variability of wind direction, humidity, and cloud forma-
tion ?

16. What were the general atmospheric conditions for the
several days preceding and succeeding the day of the storm ?

17. Was there any unusual odor observed in the atmosphere
on the day of the storm ? Describe it.

18. Report any loss of life and the destruction of buildings.

19. Furnish authentic record (written or published) of storm
when possible.

20. For how long a period did evidences of the storm remain ?

21. What speculations have been indulged in concerning the
nature of '^windfalls," and the causes which resulted in the for-
mation of such paths of destruction ?

22. In the event of copying data from permanent records
(books, newspaper files, etc.), give name of publication, volume,
page, and date of issue.

23. Enumerate and describe particular and peculiar evidences
of the storm's violence, such as : objects carried long distances ;
scars upon trees or other objects ; bowlders moved from their
beds ; trees torn from the earth or twisted off near the ground ;
pieces of timber imbedded in trees or stumps, or in the earth,
etc., etc.

24. Furnish post-office address of any person who may be pos-
sessed of information concerning "windfalls."

25. Do not fail to furnish any clue, however slight, which
may eventually lead to a discovery of the complete record of a
"windfall."

MISCELLANEOUS QUESTIONS.

1. If not individually prepared to answer any or all of the
above questions, please call to your aid such persons as may, in
your judgment, be able to render you assistance.

2. Send any newspaper article concerning this storm or others
which have occurred during this season.

3. Give name and address of any one in your State who is in
the habit of keeping a meteorological record.

i89

4. If possible, try and secure the co-operation of some intelli-
gent person, who, at the time of its occurrence, was situated
either in the path of the tornado or on the outer edge of it, and
who will be willing to furnish a narrative of the result of his ob-
servations.

GENERAL INSTRUCTIONS TO VOLUNTARY
TORNADO REPORTERS.

1. The following instructions are issued for the specific ob-
servance of voluntary Tornado Reporters for the Signal Service :

2. Report the occurrence of all local wind-storms.

3. Reports are to be rendered in accordance with the terms
of this circular.

4. All reports should be rendered as soon as possible after the
occurrence of a storm.

5. No instruments are absolutely needed but the wind- vane
and the thermometer. This office can furnish a standard ther-
mometer (compared and corrected) at cost. An ordinary
thermometer which can be procured in any village, at small
cost, will have to answer if a standard instrument cannot be
purchased.

6. A price-list of standard meteorological instruments, appa-
ratus, text-books, forms, and publications is furnished to all
Reporters in Tornado Circular No. VI.

7. The back of Tornado Circular No. V. (new series) indicates
the character of the observations to be taken and recorded.

8. Whenever, in the judgment of the Reporter, the atmos-
pheric conditions at his station are such as to portend a violent
storm, he should immediately commence observations and record
them on back of Tornado Circular No. V. (new series).

9. The only observations imperatively necessary are tempera-
ture, wind direction, and clouds. Humidity is desirable, but an
additional thermometer of standard pattern (to form the hy-
grometer) would be required.

10. For observations on wind direction a wind- vane can be
furnished by this office at cost, but it is rather expensive. In
lieu of this, it is sufficient to erect a cheap vane upon some

igo

prominent structure near at hand, where the instrument will not
be affected in its indications by surrounding objects. It is pre-
sumed, however, that Reporters will not need to resort to this
expense, as at every station suitable wind vanes will very likely
be found, either upon residences or public buildings, that will
answer every purpose.

11. Cloud directions must be observed independently of the
wind-vane. It will require some experience to observe these
directions accurately. There may be instances in unusual storms
where three or more strata of clouds will be found coursing in as
many different directions. It is very important to distinguish
the various directions, and describe the character of the clouds
in each current. The directions are best observed by comparing
the clouds with some fixed object above the observer, such as a
distant steeple or tree-top, or the cornice cf a building.

12. The wind is an important element in tornado investiga-
tion. Each Reporter is requested to use the best means at hand
for ascertaining the force of the wind in any particular instance,
and clearly state the methods by which his results were derived.
The strength of the wind is expressed in two ways — either (a)
by descriptive terms, such as light, gale, hurricane, etc., see the
tables of terms of this circular, or (d) numerically, by one of two
methods: (i) the force or pressure in pounds per square foot;
(2) the velocity in miles per hour. These numerical methods
imply the use of anemometers, but in no case should the ob-
server omit the descriptive terms. Observers who experience
the very destructive winds of the tornado's vortex should also
give such measures of the weight and dimensions of heavy objects
blown about by the wind as will give a basis for calculating the
force required to move them.

13. Hourly observations are desirable for the eight (8) hours
immediately preceding a storm, and for the five (5) hours directly
succeeding it. Under the usual conditions for local wind-storms
this division of time would bring the first observation about 8
A. M. and the last about 9 P. M. But these times will differ more
or less according to the peculiarities of each storm.

14. Observations at the following hours are desirable for every
day on which the conditions are even slightly favorable for tor-

191

nadoes: 7 A. M., 10 A. M., 12 noon, 2 P. M., 4 P. M., and 8 P. M.

15. Where Reporters are possessed of additional instruments
to those here considered necessary, they may report the observa-
tions taken with such instruments, and blank space will be found
on back of Circular No. V. (new series) for their record.

16. If Reporters have no instruments, and cannot afford to
purchase any, this fact will not wholly incapacitate them for the
duties involved in their position. A large proportion of the
most important results are to be accomplished by simple obser-
vation and careful examination.

17. Reporters are informed that suggestions from them relat-
ing to any improvement in the work of investigation will be
gladly accepted and carefully considered.

18. Further instructions will be issued from time to time as
the exigencies of the work demand.

19. It is needless to place postage stamps upon the penalty-
stamped envelopes and wrappers furnished by this office. The
printed stamp on the upper right-hand corner of the envelope or
wrapper is all-sufficient for mailing any communication or
printed matter relating to official duties.

20. Tornado Circular No. V. (new series) will be used in con-
nection with the general instructions herein contained, which
will govern the conduct of tornado investigation.

21. A special description of every tornado is desired. The
following remarks are submitted as helpful in guiding the ob-
server : If a complete account of the entire track of a tornado is
undertaken, let the observer be very careful to state as accurately
as possible the place of beginning. This location is not neces-
sarily where the tornado-cloud first descended to the earth
(although it may be), but, more truly, it is that particular spot
or portion of country over which (perhaps at a great height
above the earth) the funnel-shaped cloud was first seen to form.

22. Having found the place of commencertient, carefully as-
certain all the prehminary conditions of atmospheric changes
existing prior to the development of the tornado-cloud. In
determining the exact locality of final disappearance, exercise con-
siderable vigilance, for you may most easily be deceived. It is
a characteristic feature of the tornado -cloud to rise suddenly from

192

the earth, and, continuing its northeastward course in the lower
regions of the atmosphere, again reaching terra Jirma after an
interval of several miles. You may find a number of these gaps
along the tornado track you are examining, but do not mistake
them for points of termination ; rather look upon their appear-
ance as suggestive of a subsequent re-appearance rather than dis-
appearance. If these gaps occur in consecutive order as to time
and place, pursuing, when taken together, a northeastward trend,
and the difference in time of disappearance and re-appearance at
each interval accounts for the passage of that interval, there can
be no doubt of their forming disconnected parts of one and the
same tornado track. The invariable accompaniment of a tornado
is the hailstorm, vi\\\Qh precedes its first appearance, and succeeds
its final disappearance. This characteristic should be carefully
watched for and any peculiarity minutely recorded.

23. Tornado features are peculiar in that they ^lxq particular
rather than general. In regard to information, the test of de-
sirability is reached, not so much by the quantity as the char-
acter of the data given. It is absolutely necessary to success, in
securing precisely the information desired, that every observer
should have at his command a code of definite instructions. By
this means he will realize the necessity for the various lists of
questions, their independent use, and prepare himself to under-
take an intelligent examination of the tornado's path. It is not
expected that every observer will find it possible to answer all
the questions in any of the lists, because of the necessarily im-
perfect opportunities for observation incident to each locality.
It is assumed, however, that if the conditions for observation
were complete, every question could be readily answered.

24. The path of the storm should be divided by longitudinal
lines into three portions parallel to the direction of progress :
these will be designated as the center belt, the right side, the
left side. These latter may be subdivided into belts of greatest
or least disturbance.

25. Wherever reference is made to areas of destruction, or
where prostrations are described, the part of the path in which
the destruction occurred, or in which the debris was found,
should always be mentioned.

193

26. To avoid confusion, no terms should be used to indicate
the sides of the tornado track except right " and " left."

27. The direction of all prostrated objects should be carefulty
given ; if they have subsequently been moved by a force different
from that which threw them down, or should the same force
continue to act in successively different directions, such separate
causes should be carefully distinguished.

28. The track of the tornado should be examined continuously
throughout, and not here and there. The examinations should
also be carried beyond the path of greatest violence ; for, al-
though no trees or houses may have been there destroyed, valu-
able evidence to show the mode of action can often be obtained.

29. Groups of trees lying upon each other should receive care-
ful attention, and distinctions should be made between the top
and bottom prostrations, and their several directions.

30. The topography of the ground over which the tornado
has passed, and especially of that where destruction begins,
should be observed. The comparative destruction on hilly and
level ground should also be noted.

31. The atmospheric conditions before and after the appear-
ance of the tornado, especially the presence of a thunder-storm,
its severity, extent, and the contrasts of temperature north and
south of the central area should be ascertained.

32. When prostrations are described on either side of the
storm's track, or at the center, their relative positions, either re-
specting each other, the sides of the storm's path, or the center,
should be stated.

33. The distance at which the surrounding currents of air are
sensibly influenced by the cloud vortex ought to be determined,
and also it should be noted whether or not any previously exist-
ing currents were immediately, or during the passage of the
tornado, changed in their direction.

34. The currents of air on the two sides, and their relative
directions and forces, should be carefully mentioned; also the
currents of the center, whether upward, downward, or rotary.

35. Any unusual manifestation of force on either side of the
track, the width and direction of the path of destruction, the
character of the ground passed over, and also of that in the .im-

194

mediate vicinity, and the direction, force, and temperature of
currents of air should be given.

36. All explosions, the side on which they occurred, the di-
rection and force of the wind at the time, and the character of
the ground in their vicinity should be noted.

37. The place, date, time, and direction of the tornado are
essential.

38. Observers should state the width and length of the track,
giving, in the former instance, not only the entire breadth of the
path of destruction, but of that part over which the greatest
violence was exerted.

39. The velocity and duration of the storm, and the shortest
time it consumes in passing any one point, are important facts.

40. The form of the tornado-cloud, its motion, direction, and
velocity (estimating the latter approximately, if it cannot be
determined accurately, by its action upon surrounding objects)
should be given.

41. All air-currents which have been instrumental in directly
causing destruction are important facts.

42. The direction and velocity with which the clouds, if there
were any, were seen to approach before the beginning of the
tornado, or any strange and violent agitation of the atmosphere
noticed at the time, ought to be noticed.

43. The appearance and disappearance of the cloud vortex,
the character of the section of country over which it disappears,
and the conditions of the surface at the points of its departure
and return should be noted.

44. The occurrence of thunder and lightning, and all evi
dences of electrical action, particularly within the tornado-cloud,
should be given.

45. Particular attention should be paid to the peculiar rum-
bling noise attending the progress of the tornado, its duration,
intensity, and the distance at which it can be heard.

46. The precipitation of hail and rain, the time of its occur-
rence, whether before, after, or during the passage of the tor-
nado-cloud, the side on which it fell, and the direction of the
wind at the time, are necessary elements of the investigation.

195

47. Efforts should be made to gather all available data regard-
ing cloud formation, so that when opportunity is offered any
peculiar development may be preserved by means of a sketch
made at the time the information was obtained.

48. In all attempts at sketching a tornado-cloud, particular
attention should be given to illustrating the peculiar whirl of the
cloud, so that the sketch shall show whether the direction was
from right to left or the reverse.

49. In all sketches of whatever nature, the supposed center
of the storm's path should always be indicated by a long arrow
pointing in the direction of the storm's progressive movement,
so that the relative position of the objects acted upon as com-
pared with that of the tornado's track may be known.

50. Every effort should be made to obtain temperature records,
particularly where observations have been taken on opposite
sides of the storm's path ; the time of day and the accompanying
wind direction are indispensable facts in connection with these
observations.

51. It is of great importance that trustworthy data concerning
the prevailing direction of the wind over the section of country
traversed by the storm (together with the temperature), for at
least ten days before the storm, should be obtained.

52. In entering upon the work of investigation, it is necessary
that the observer begin his labors as near as possible to the sup-
posed origin or first appearance of the storm, and then trace the
phenomena in regular order.

Such method will often provide the explanation of anomalous
effects, and materially assist him in following a train of sequences,
watching the successive disclosures of the various features of
cloud formation and attendant wind directions.

Much or most of this valuable information would be lost or
seriously confused by any other mode of examining the storm's

JOHN P. FINLEY,
2d Lieut., Signal Corps, U. S. A., and Assistant.
Prepared under the direction of —

Brig, and Bvt. Maj. Gen'l W. B. HAZEN,

Chief Signal Officer of the Army»

196

TORNADO INVESTIGATION.

Some of the results sought to be attained by a systematic study of
tornadoes may be briefly given as follows : —

(i.) To determine the origin of tornadoes and their relation to other
atmospheric phenomena.

(2 .) To determine the geographical distribution of tornadoes and their
relative frequency of occurrence in different States, and in different parts
of the same States.

(3.) To determine the conditions of formation, with a view to the pre-
diction of tornadoes.

(4. ) To determine the means of protection for life and property.

(5.) To determine the periodicity of the occurrence of tornadoes, and
their relative frequency by seasons, months, parts of a month, and time
of day.

(6.) To determine the prevailing characteristics of tornadoes.
(7. ) To determine the relation of tornado regions to areas of baromet-
ric minimum.

(8. ) To ascertain yearly the loss of life and property in the various
tornado districts, and its effect upon the industries of the people.

(9.) To ascertam the influence of topography upon the occurrence and
movement of tornadoes.

(10.) To determine the influence of rainfall and forests upon the
development of tornadoes.

(II.) To ascertain the relations of tornadoes to hailstorms, thunder-
storms, and hurricanes.

The following are most of the features of map study that must receive
consideration in the preparation of a tornado prediction for any day : —

(i.) Barometric Trough. Region. Ratio of Axis. Pressure. De-
parture from Normal.

(2.) Central Area of Barometric minimum. Region. Pressure.
Departure from Normal.

(3.) High Contrasts of Temperature. Region. Gradient.

(4.) High Contrasts of Cold Northerly and Warm Southerly Winds.
Region.

(5.) High Contrasts of Dew-point. Region. Gradient.
(6. ) Heaviest Lower Cloud Formation. Region. Kind.
(7.) Opposing Movement of Lower Clouds. Region. Directions.
(8.) Coincident Movement of Upper and Lower Clouds. Region.
Direction.

(9.) Opposing Movement of Upper and Lower Clouds. Region.
Direction.

(10.) Opposing Movement of Lower Clouds and Winds. Region.
Direction.

3na
3iva

3iva

•AjBjqii en; o; }! eujBuuq Aq peMeusj eq Ablu
;! pioq uo ^ou ^| ./sna 9;Ba„ jepun peduuB^s e^ep ;sb| 9L|;
uo AdVdan SIAVa d d3inVM ©mi 1B anp S! >iooq siMi

UDOS

DidOHHXNviiHd QMV Diioanvia
SHX AS aaAvoQNa

VNno-avD HX'aoM

JO AXISH3AINa
3HX JO AHV^an 3HX

Internet Archive Audio

Featured

Top

Images

Featured

Top

Software

Featured

Top

Texts

Featured

Top

Video

Featured

Top

Mobile Apps

Browser Extensions

Archive-It Subscription

Save Page Now

Full text of "Tornadoes, what they are and how to observe them, with practical suggestions for the protection of life and property"

See other formats